June 2016 Physics Regents Exam Explained By Jillian

June 2016 Physics Regents Exam Explained By: Jillian Quinn

The answer is #4 - weight • A vector is a quantity that has magnitude and direction. • Power, kinetic energy and speed are scalars because they have magnitude but no direction. • Scalars are described using only numbers (magnitude). • Scalars have one characteristic while vectors have two. • Weight has both magnitude and direction because it is a force. • Weight is mass times gravitational acceleration and normally in the downward direction because of gravity.

The answer is #2 - 65. 0 kg • Conservation of mass is a principle that states mass can not be created or destroyed. • The astronaut’s mass is 65. 0 kg where-ever they are. • The difference between the astronaut on the Earth and the Moon is the weight. • Weight is the amount of force that gravity has on an object. • Mass is a measure of the amount of matter something is made up of. • The gravity on the Moon is less than the gravity on Earth.

• Mass of the astronaut-On Earth = 65. 0 kg -On the Moon = 65. 0 kg • Weight of the astronaut-On Earth -On the Moon

The answer is #4 - may be moving at a constant speed • Net force is the vector sum of the forces acting on a particle or body. • An objects velocity does not change if and only if the net force acting on the object is zero. • If the net force on an object is zero, its speed and direction of motion do not change. • So when the sum of the forces acting on the block is zero, it may be moving at constant speed. • Constant speed means that you are moving the same distance every second, so the speed does not change at all. • The acceleration is zero when there is constant velocity.

The answer is #1 - mass of the object from 1. 0 kg to 2. 0 kg • Inertia is the name for the tendency of an object in motion to remain in motion, or an object at rest to remain at rest unless acted upon by a force. • The more inertia an object has, the more mass it has. • Inertia is a force that keeps stationary objects at rest and moving objects in motion. • Newton’s 1 st Law of Motion states that an object will remain at rest or in uniform motion in a straight line unless acted upon by an outside force.

• Objects with a greater mass have more inertia 1 mass increases 2 net force applied increases 3 time net force applied increases 4 speed increases

The answer is #3 - 60 N • Newton’s 3 rd Law states for every action there is an equal and opposite reaction. • So if the horse exerts a force of 60 N onto the cart then the cart exerts a force of 60 N back onto the horse. • The size of the force on the first object equals the size of the force on the second object. • The action and reaction are equal and opposite.

60 newton force

The answer is #2 - mechanical and longitudinal • A wave is a vibratory disturbance that propagates through a medium. • Mechanical waves need a medium to travel through like air or water(ex. sound and water waves). • A longitudinal wave a wave in which the motion of the vibration is parallel to the direction of wave travel(ex. sound waves, compression waves in a spring and earthquake p waves). • Sound waves are both mechanical and longitudinal. • Electromagnetic waves do not need a medium to travel through and can travel through a vacuum. • The motion of the vibration of traverse waves is perpendicular to the wave.

• Sound waves are not electromagnetic or transverse so that narrows down the choice. 1 mechanical and transverse 2 mechanical and longitudinal 3 electromagnetic and transverse 4 electromagnetic and longitudunal

The answer is #2 - 2. 0 x 10^-5 N • An electric force is the repulsive or attractive interaction between any two charged bodies. • Coulomb’s law is an experimental law of physics that quantifies the amount of force between two stationary, electrically charged particles. • The electric force between charged bodies at rest is conventionally called electrostatic force or Coulomb force.

The formula for Coulomb’s Law

The answer is #1 - 1. 0 kg x m/s • Momentum is the quantity of motion of a moving body, measured as a product of its mass and velocity. • When two objects collide the total momentum before the collision is equal to the total momentum after the collision. • P= momentum • P= mv • Pbefore = Pafter or P=P’

The answer is #2 • Friction is the force of resistance that holds back and acts on an object in motion. • The direction that friction acts in is the opposite direction that the object is going.

The answer is #3 - protons • A magnetic field is a region around a magnetic material or a moving electric charge within which the force of magnetism acts. • Protons are responsible for the magnetic field. • Magnetic fields are produced by moving electric charges. • A moving stream of electrons will produce a magnetic field. • Magnetic fields are like electric fields or gravitational fields in that they allow magnets to interact without touching.

A magnetic field is an area where an object shows the influence of a magnet.

The answer is #3 - A is negative and B is negative • An electric field surrounds an electric charge, and exerts force on other charges in the field, attracting or repelling them. • Electric fields are created by electric charges, or by time-varying magnetic fields. • The lines are directed away from positively charged sources and towards negatively charged sources. • From positive to negative.

The answer is #2 - 100 J • Work is the product of force and displacement. • Work is a measure of energy transfer that occurs when an object is moved over a distance by an external force at least part of which is applied in the direction of the displacement. • W=Fd • Work transfers energy from one place to another, or one form to another. • Work is measured in joules.

The answer is #2 - 15 J • Work is the product of force and displacement. • Kinetic energy is the energy of an object in motion. • In regards to the acceleration of the block, acceleration is a change in speed. • Work done on the object = change in kinetic energy of the object • If the work done on the object was 15 J, then the change in kinetic energy is 15 J. • This question may be over thought but because there is no friction and the work done on the block is 15 J, then the change in kinetic energy is 15 J.

The answer is #2 - 2 PE • Potential energy is stored energy. • Gravitational potential energy is energy an object possesses because of its position in a gravitational field. • PE=(1/2)mgh • Potential energy is the product of a half mass, gravity and height. • They gave us in the question that the objects are at the same height and have the same gravity, so the only difference is the mass.

The answer is #3 - 2. 2 x 10^3 J • Kinetic energy is the energy of an object in motion. • It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. • Work measures the energy transfer that occurs when an object is moved over a distance by an external force at least part of which is applied in the direction of the displacement. • KE=(1/2)mv^2

The answer is #1 - nature of the medium • A wave is a vibratory disturbance that propagates through a medium (body of matter) or field. • Waves only transfer energy not mass. • Electromagnetic waves do not need a medium to travel through and can travel through a vacuum. • Wave speed is the distance a wave travels in a certain amount of time. • The speed od a wave mostly depends on the medium or matter that the wave travels through.

The answer is #3 - 96 W • Work is a force that causes a displacement or movement of an object. • Power is the rate of doing work. • Power is the work done over time. • We are given the work done and the time it took to do that work.

The answer is #3 - 2. 8 m/s • Power is the rate at which work is done. • In this question we can find the velocity by dividing the power of the elevator motor by the weight of the elevator. • Constant speed means the elevator is traveling the same distance each second. • They gave us the power of the elevator in watts and the weight of the elevator in newtons. • This question uses the power and weight of the elevator to find the speed.

• We need to find the maximum constant speed of the elevator

The answer is #4 - high frequency • Radio waves are electromagnetic waves meaning they do not need a medium to travel through and can travel through a vacuum. • The frequency of waves is the number of cycles per second. • The wavelength of a wave is the length of one complete wave cycle. • The period of a wave is the time it takes to complete 1 wave cycle. • When radio waves emitted from a radar gun hit an object that is moving toward the patrol vehicle, the returning frequency will be higher than the original. • When the signal hits that vehicle that is moving away from the observer, the returning frequency will be lower than the original one. • The frequency change can be used to determine the speed of the target vehicle.

The answer is #1 - energy, only • A wave is a vibratory disturbance that propagates through a medium (body of matter) or field. • Waves transmit energy not mass. • Waves transfer energy from one place to another by repeated small vibrations of particles. • Light waves are electromagnetic waves meaning they do not need a medium to travel through and can travel through a vacuum. • The frequency of light determines its color.

The answer is #3 - period • The period of a wave is the time it takes to complete 1 wave cycle. • The period is found by dividing 1 by the frequency. • The symbol for the period of a wave is T. • The frequency is how many wave cycles per second occur. • But the period lets us know the time for just 1 wave cycle.

1 amplitude- height of the wave 2 frequency- how many wave cycles per second 3 period- time required to produce one wave 4 wavelength- length of one complete wave cycle

The answer is #4 - The current in the wire produces a magnetic field that exerts the force on the compass needle • The Earth has a magnetic field. • A compass indicates the direction of magnetic north, which is not quite true north. • A charged object in motion creates a magnetic field. • Current is the flow of electrons which is a moving charged object. • Current in a wire produces a magnetic field around the wire. • A compass can be used to detect a magnetic field around a wire that had current flowing through it. • Current carrying wires feel an external force when near a magnetic field.

The answer is #2 - 393 nm • Wavelength is the length of one wave cycle. • Lucite has an index of refraction of 1. 5. • Lucite is material found in the reference table under the absolute indices of refraction. • They gave us the wavelength of a beam of monochromatic light in air. • Wavelength is the quotient of velocity divided by frequency. • First, we need to find the speed of light in Lucite. • Then we will use the number we got and plug it into the wavelength formula with the frequency they gave us.

First, we need to find the speed of light in Lucite.

Now we need to find the wavelength.

The answer is #1 - loudness • Amplitude is the height of a wave. • A wave is a vibratory disturbance that propagates through a medium or field. • The amplitude in a wave shows the amount of energy it has. • In sound, amplitude represents loudness. • Sound are vibrations that are heard when they reach someone’s ears. • The more amplitude a sound wave has, the louder it will be. • The less amplitude a sound wave has, the quieter it will be.

The answer is #2 - the same magnitude, but the opposite direction • An electric field is a region around a charged particle or object within which a force would be exerted on other charged particles or objects. • Electrostatic force is a force of attraction or repulsion between two electrically charged objects. • The parallel plates have equal and opposite charges. • Therefore the electrostatic forces have the same magnitude or amount of force, but opposite directions because they have opposite charges.

The answer is #1 - interference • Interference is the effect produced by two waves passing simultaneously through a region. • The principle of superposition states that the combined displacement of the two interfering waves is the algebraic sum. • There is both constructive interference and destructive interference. • Constructive is the combination of two waves in the same phrase. • Destructive is the combination of the two waves that are 180 degrees out of phase. • Sound waves are mechanical waves that need a medium to travel through.

• 1 interference- effect produced when two or more wave pass simultaneously through the same point. • 2 diffraction- is the spreading out of a wave into a region beyond an obstacle. • 3 refraction- is the bending of a wave when it enters a medium where its speed is different. • 4 resonance- is the tendency of a system to vibrate with increasing amplitudes at some frequencies of excitation.

The answer is #3 - longer wavelength and less energy • A photon is a particle representing a quantum of light or other electromagnetic radiation. • A photon carries energy proportional to the radiation frequency but has zero rest mass. • Based on the electromagnetic spectrum in the reference table, microwaves have a longer wavelength and less energy than gamma rays. • Microwaves and gamma rays are different types of radiation. • Gamma rays are the most energetic and have the shortest wavelength.

The answer is #1 - lepton • A neutrino is a neutral subatomic particle with a mass close to zero and half-integral spin, rarely reacting with normal matter. • Three kinds of neutrinos are known, associated with the electron, muon, and tau particle. • The Standard Model of Particle Physics is a set of mathematical formulae and measurements describing elementary particles and their interactions. • The Standard Model characterizes elementary particles. • A neutrino is a type of lepton. • A lepton is an elementary particle of half-integer spin that does not undergo strong interactions.

A neutrino is a type of lepton.

The answer is #3 - uds • A quark is a type of elementary particle and a fundamental constituent of matter. • Quarks combine to form composite particles called hadrons, the most stable of which are protons and neutrons, the components of atomic nuclei. • Baryons are relatively large subatomic particles. • Quarks make up baryons. • To make it neutral, the sum of the quarks must be zero.

1 cts charm(+2/3 e) + top(+2/3 e) + strange(-1/3 e) = 1 2 dsb down(-1/3 e) + strange(-1/3 e) + bottom(-1/3 e) = -1 3 uds up(+2/3 e) + down(-1/3 e) + strange(-1/3 e) = 0 4 uct up(+2/3 e) + charm(+2/3 e) + top(+2/3 e) = 2

The answer is #2 - 1. 8 x 10^1 J • Matter is anything that has mass and takes up space. • Energy is the quantitative property that must be transferred to an object in order to perform work on, or to heat, the object. • Energy and matter are directly proportional. • We need to use Einstein's equation, E=mc^2. • The question is asking how much energy is released when the matter is converted to energy. • We are given the mass and c is a constant found in the reference table.

The answer is #2 - 6. 4 m/s • Initial speed is the speed of an object at the beginning of the measurement. • We are given the initial speed and are asked to find the speed of the ball 2. 2 seconds after was hit. • We will need to use the equation Vf = Vi + at • Acceleration is a constant in this question and negative because the ball is slowing down (-9. 8 m/s^2) • Final velocity or speed is the speed of the object at the end of the measurement.

The answer is #4 - 13. 5 e. V • The equation E = q. V is needed for this question. • E is the electrical potential energy. • Q is the charge. • V is the potential difference. • They gave us the charge and the potential difference, so we need to find the electrical potential difference. • Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field. • Potential difference is the difference of electrical potential between two points. • Electrical potential difference is also known as voltage.

The answer is #3 • The electrical resistance of a circuit component or device is defined as the ratio of the voltage applied to the electric current which flows through it. • Ohm’s law is a law stating that electric current is proportional to voltage and inversely proportional to resistance. • The ohm is the symbol for resistance. • There are series circuits and parallel circuits. • For the resistance of series, add the resistances up. • For parallel, 1/resistance = 1/r 1 + 1/r 2 … • Answer 3 is a series circuit and has the greatest resistance.

The answer is #3 • A transverse wave is a wave vibrating at right angles to the direction of its propagation. • If a transverse wave is moving in the positive x-direction, its oscillations are in up and down directions that lie in the y–z plane. • Since the wave is moving to the right, the particles are moving up and down. • Particle x is on the higher side of the wave, so the motion of particle x at the instant shown is up.

The answer is #4 • Opposites attract, so since they are both N’s, they are repelling each other. • Magnetic field lines represent magnetic fields. • A magnetic field describes the magnetic influence of electric charges in relative motion and magnetized materials. • Magnetic fields flow from north to south. • Answer 4 is correct because the norths are repelling each other and flowing away.

The answer is #2 - the width of a student’s finger • The measurement they gave us is 1 x 10^-2 meters. • 1 meter is 3 feet and our number is. 001 meters. • That means our number is. 003 feet. • That should rule out answers 3 and 4. • Then there are 12 inches in a foot, so our number is around. 036 inches. • That rules out answer 1, so the answer is the measurement is closest to the width of a student’s finger.

The answer is #4 • Speed is how fast the about is going. • Time is how long it has been falling for. • Speed and time are directly proportional for a freely falling object. • The object is accelerating when falling so both time and speed are increasing. • The line on the graph should be diagonal due to the circumstances.

The answer is #4 - 2. 3 x 10^5 J • The electrical resistance of a circuit component or device is defined as the ratio of the voltage applied to the electric current which flows through it. • We are given resistance(9. 6 ohms), v(120 volts) and time(2. 5 minutes). • We need to find E, the total electrical energy. • First, we need to find the power used by the hair dryer. • Power = v^2 over r • Then use the P and plug it into E=Pt.

The answer is #3 - 42 N • They gave us the weight of the box and an angle so we can use trig to solve this one. • They want us to find the component of the side perpendicular to the incline.

The answer is #2 • Having a positive velocity means the object is moving forward. • But having a negative acceleration means the object is slowing down. • The graphs in this question have the relationship of position and given with their specified conditions. • Graph 2 is correct because the position of the object is still moving forward so the graph has a positive slope, but the object is slowing down with time the so graph is curved.

The answer is #3 - 800 m • We are asked to find the distance it will take for car A to catch up to car B. • Car A is initially 200 meters behind car B but going 5 m/s faster than car B.

The answer is #2 - 3. 6 x 10^-2 C • Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field. • We can use the equation q = It to find the total charge. • I is the current which they gave us (2. 4 milliamperes). • T is the time which we also have (15 seconds). • The fact that it is a 2700 -ohm resistor we do not need. • We just need to convert milliamperes to amperes before we plug the numbers into the equation.

The answer is #1 - 18. 0 m/s east • An impulse is a change in momentum. • Momentum is mass in motion. • Momentum is the product of mass and velocity. • P stands for momentum. • They gave us the mass of the car (1000 kg) and the velocity of the car before the impulse. • In order to find the velocity after the impulse, we will need to use the equation Pbefore = Pafter.

The answer is #1 • Potential difference is the difference of electrical potential between two points. • Current is the rate of flow of charge. • The current flowing through a resistor at a constant temperature is directly proportional to the potential difference across it. • The line of the graph of potential difference and current is a diagonal. • Both current and potential difference increase proportionally.

The answer is #4 - 4 R • Resistance is voltage divided by current. • Long, thin and hot wires have high resistance. • Short, fat and cold wires have low resistance. • In this question, the tungsten wire that is longer and thinner has higher resistance. • We need to use the equation R = p. L/A • P is resistivity, l is length and A is area. • P is the same for each of the wires so we do not need to worry about it. • So if we double the length and halve the area, we get 2/0. 5 which is 4. • The resistance of the second wire is 4 R.

The answer is #1 - the resistance increases and the current decreases • Current is the flow of electrons. • Resistance is a measure of the opposition to current flow in an electrical circuit. • Materials with low resistance, have better electron flow. • If temperature increases, then resistance increases. • Hot, thin and long wires have high resistance. • So if the resistance increases, that means that the current decreases because they are opposites.

The answer is #2 • Diffraction is the spreading out of a wave into a region beyond an obstacle. • The amount of diffraction depends on the wavelength and size of opening. • The greatest diffraction occurs when the size of the opening is about the same size as the wavelength and the longer the wavelength. • Choice 2 has a longer wavelength and the opening is about the same size as the wavelength.

The answer is #3 - 1. 03 x 10^3 Hz • Every elastic object has a particular frequency at which it will vibrate at if struck and that is its natural frequency. • The singer can shatter the glass by maintaining a note with a frequency equal to the natural frequency of the glass. • The frequency is equal to velocity divided by wavelength. • The speed of sound in air at STP is 331 m/s (found in the reference table). • They gave us the wavelength to be 0. 32 meters.

The answer is #3 - antinodes B and D • Interference is the effect produced by two waves passing simultaneously through a region. • Constructive interference is the combination of two waves in the same phase. • A node is a point on a wave with minimal amplitude. • An antinode has maximum amplitude. • In the picture B and D are in phase with each other because they are in the same positions in their cycles. • 3 is the correct answer because constructive interference is occurring and the antinodes make it maximum.

The answer is #3 • Potential difference is the difference in the amount of energy that charge carriers have between two points in a circuit. • Voltmeters are always placed in parallel with the circuit element being analyzed. • In choice 3, the voltmeter is parallel to both the resistors and closest to R 2 which they can then measure the potential difference of.

The net force is 5. 0 N • The net force is the sum of the forces acting on the particle or body. • We are given that the mass of the box (2. 5 kg), that there is a force of 15 N pointed to the right and the box is accelerating 2. 0 m/s^2 to the right. • The net force is equal to mass times acceleration. • We were given both force and acceleration. • For this section of the problem we did not need that there was a constant force of 15 N. • The work needed is in the next slide.

The force of friction is 10 N • In this part of the question they want to know the force of friction. • We know the mass of the box, the constant force, the acceleration of the box and the net force. • A force of friction is any force that opposes motion due to contact with other bodies. • The force of friction is the difference in the net force and the constant force.

The absolute index of refraction of the mineral is 1. 9 or 2. 0 • The index of refraction is a measure of the bending of a ray of light when passing from one medium into another. • n is the abbreviation for absolute index of refraction. • The absolute index of refraction of water is 1. 33 • The angle of incidence is 27 degrees. • The angle of refraction is 41 degrees. • We need to use the equation

The height of the table is 0. 750 meters • For this question we need to find the distance or height of the table. • They gave us the initial velocity, time and acceleration is a constant. • The ball accelerates on the way down so we also need acceleration. • The ball has an initial velocity of 2. 5 m/s. • The time it took is 0. 391 seconds. • Acceleration is 9. 81 m/s^2. • The equation we need to use is

The measured times are the same • For this part of the question we know the height of the table, the initial velocity and acceleration. • We need to compare the time it took the ball to reach the floor for trail A and trial B. • The time of trial B is based on the height of the table and since each of the trials had the same table heights, their measured times are the same. • The table heights for each were 0. 75 meters and so the time for each is 0. 391 seconds.

The speed of the airplane is 14 m/s • We are asked to find the speed of the airplane given the radius and acceleration. • We will use the equation specific to circular motion. • The equation just needs to be solved for velocity.

The airplanes velocity is east at the intstant • There are 2 vectors that describe circular motion. • Centripetal acceleration goes toward the center of the circle. • Velocity forms a 90 degree angle with centripetal acceleration. • Velocity goes straight outward in the direction the object is going. • The centripetal acceleration is south in the top airplane. • The means the velocity is in the east direction.

Acceleration or rate of change of velocity is represented • The graph has speed and time. • Acceleration is represented because it is a change in speed which takes time. • In this question, time is on the x axis and speed is on the y axis. • The speed moving changes with time. • Since the speed is moving, there is a change is velocity or an acceleration.

The distance the marble travels is 6. 0 m or 5. 9 m • To find the distance we can use the equation • We know the time the marble travels and can use the graph to find the acceleration. • Acceleration is change in velocity over time.

The acceleration due to gravity is 3. 0 m/s^2 • Acceleration due to gravity is the weight or force due to gravity over mass. • This graph represents weight vs. mass. • So we need to pick a good point on the graph to get the numbers for the equation. • I picked 6 N on the y axis (weight) and the mass on the x axis was 2 kg.

1. 0 cm = 0. 40 km • For this question I need to measure the vector diagram. • For the bottom line of the vector, I measured 5. 0 cm = 2. 0 km. • So to find how many km 1. 0 cm is, I have to divide the 2 km by the 5. 0 cm I measured. • 2. 0 km divided by 5. 0 cm is 0. 40 km. • So 1. 0 cm = 0. 40 km.

The resultant vector should be approximately 6. 1 cm long • The resultant vector is a combination of the two vectors that they gave us in the diagram. • To form the resultant vector, we need to connect the vector diagram. • The resultant vector should make the diagram look like a triangle but have arrows for the direction the hiker went. • The length of the resultant vector can be found using trig.

The resultant displacement is 2. 4 km • The resultant displacement is the length of the resultant vector. • We used trig in the last question to find the length of the resultant vector. • The resultant displacement is 2. 4 km which is 6. 1 cm.

The angle is 35 degrees

The spring constant is 170 N/m • The spring constant measures how stiff or strong the spring constant is. • They gave us the distance the spring is compresses and the downward force.

Elastic potential energy is 0. 42 J • Elastic potential energy is potential energy stored as a result of deformation of an elastic object, such as the stretching of a spring. • Potential energy is stored energy. • It is equal to the work done to stretch the spring, which depends upon the spring constant k as well as the distance stretched. • We have the compression of the spring, the downward force and the spring constant. • We just need the compression of the spring and the spring constant to find the elastic potential energy.

Elastic potential energy is converted to kinetic energy • Potential energy is stored energy and once the spring is in motion, it changes to kinetic energy which is energy in motion. • When the spring is inside the box, it is not in motion so there is elastic potential energy or stored energy in the spring. • When the spring is released, it is in motion, energy is motion is kinetic energy. • Energy at rest to energy in motion. • Could also convert to sound, thermal energy or gravitation potential energy.

• A circuit is a path that starts and ends in the same place. • The parts of a circuit are connected by wires. • Electricity flows through closed circuits and not open circuits. • In the question, they gave us specifications for the circuit. • Resistors are “things” in a circuit that limit current flow. They can be controlled resistors or electrical devices like light bulbs or lamps. • The lamp and resistor are connected in parallel.

The current through the lamp is 0. 50 A • The abbreviation for current is I. • Electric current (I) is the rate at which charge passes a given point in an electric circuit. • We have the electrical power of the lamp (6. 0 W) and the potential difference (12. 0 V) to find the current through the lamp. • P is electrical power and V is potential difference.

The current in the resistor is 0. 10 A • Electric current (I) is the rate at which charge passes a given point in an electric circuit. • A resistor controls the flow of current in a circuit to other parts in the circuit. • The current in the resistor is the difference between the amperes caused from the battery and the current through the lamp.

The resistance of the resistor is 120 ohms • Resistance is a measure of the opposition to current flow in an electrical circuit. • To find the resistance of the resistor we can use the equation • Resistance is potential difference over current. • We will use the potential difference of 12 V given in the question and the current in the resistor we found in the last question (0. 10 A)

The energy is 1. 89 e. V • The hydrogen energy levels are found in the reference table. • N = 3 is -1. 51 • N = 2 is -3. 4 • The difference between the energies of n=3 and n=2 is 1. 89 e. V. • In this question, the energy of an emitted photon when an electron transition occurs is 1. 89 e. V.

The energy of this emitted photon in joules is 3. 02 x 10^-19 J • One electronvolts is equal to 1. 6 x 10^-19 J. • The energy we determined in the last question was 1. 89 e. V. • So we need to convert from e. V to joules.

The frequency of the emitted photon is 4. 56 x 10^14 Hz • Frequency is the number of occurrences of a repeating event per unit of time. • What we need is found under the modern physics section of the reference table. • In the equation h is Plank’s constant, f is the frequency and Ephoton is the energy of the photon. • We found the energy in the last question (3. 02 x 10^-19 J) • Plank’s constant is in the reference table as 6. 63 x 10^-34 J/s

The color of light associated with this photon is red • For this question we need to use our answer from the last question and look at the electromagnetic spectrum in the reference table. • 4. 56 x 10^14 Hz falls under the red color of visible light category. • The color associated with the light is based on the frequency.

The End Thanks for joining me for the June 2016 Regents Physics Exam -Jillian Quinn