You need Clean paper 2 pencil Feb 28
You need: Clean paper (2) / pencil Feb. 28, 2020 HW: Net Force Practice Problems *Anything else to turn in? Progress reports? Warm Up: If I push a pencil across the table, when it leaves the table, where does it go? Why? I CAN: characterize forces (strength and direction)
FEBRUARY 2020 Sunday Monday 3 Fo/Mo Tuesday 4 Fo/Mo Wednesday 5 Fo/Mo Thursday 6 Fo/Mo Friday Saturday 7 Fo/Mo 8 African Tales Faculty game 10 Fo/Mo 11 Fo/Mo 12 13 Fo/Mo 14 Fo/Mo 15 ’s ine t n le Va 17 Fo/Mo 18 Fo/Mo 19 Fo/Mo 20 Fo/Mo 21 Fo/Mo 22 25 Fo/Energy 26 Fo/Energy 27 Fo/Energy 28 Science Day! 29 PTO meeting 24 Fo/Mo Progress Reports NJHS due Assembly (x 2)
March 2020 Sunday Monday Tuesday Wednesday Thursday Friday Saturday 1 2 3 4 5 6 7 8 9 10 11 Early Release 12 13 14 15 16 17 18 19 20 21 Color Battle Fundraiser Assembly Eo. E 22 23 24 25 26 End of Qtr 29 30 31 27 y h Tc kd r. W 28
Dr. Jennifer Rowell • • Endocrinologist Endo Ology ologist
The Endocrine System Pituitary gland – in the brain Hypothalamus gland – in the brain Thyroid gland – in the neck Thymus gland – in the chest / heart region Parathyroid gland – in the neck Pancreas– in the trunk / main body region Adrenal glands – on the top of each kidney Ovaries (girls) and sperm (boys)– in the reproductive organs
Negative Feedback Hypothalamus senses ________ cells more energy need _____ Pituitary decreases certain chemicals Pituitary increases certain chemicals cells Hypothalamus senses _______ enough energy have ________
Toilet tank You flush and the tank goes into the bowl. The tank is empty. Water turns on to fill it. When tank is full, water turns off.
Vocabulary Catch Up • • • Motion Ways to describe? Reference point Meter Metric measurement
Motion – Occurs when an object position changes _______ relative to a point _______. reference
far -Distance: how ____ an object has traveled. distance -Displacement: _______ and _______ of an object’s change in direction position from the starting point.
How can we describe motion? • Motion can be described by: – – – DISTANCE TIME SPEED DIRECTION VELOCITY (speed AND direction) ACCELERATION (change in VELOCITY)
Conversion in the METRIC system… NAME! Kilo km Hecto Deka hm dkm LEFT Meter Liter Gram RIGHT deci dm centi cm milli mm
Speed – the _________ distance an object time travels per unit of _________. Also known as the ______ of change in rate position.
Vocabulary Catch Up • Speed – Instantaneous – Average – Constant • Velocity • Acceleration • Independent and dependent axes • Straight = constant • Curved = changing • Slope = speed • Horizontal = no motion
In math terms… • A “change in position over time” is the same as saying:
Speed, Distance & Time Speed = Distance Time D S T Time = Distance Speed Distance = Speed x Time
of e tur iew… a r N Rev e t Af ces r Fo Graph Story cut/paste • Each student gets his/her own copy of the red “answer” rectangles and the white “question” graphs.
Graph Story cut/paste • Glue the story in place – but only after you are SURE it is the best placement. • Share the glue sticks – and leave them in good Ms. Gar working order. ris co llec will t on We dne sda y.
On the back of your warm up… Sketch the graph and list these words. Label each word with the letter you believe it matches. Stationary: _____ Increasing speed: ____ Slow and constant: ____ Fast and constant: ____ Returning home: _____ E For example, line segment “E” has a decrease in distance so it must be going back or returning to home.
Now, let’s collect them. Put your name on your paper!
Christy wanted to visit the zoo, which was 20 kilometers away from her house. To help her get there, her mother drove her to the bus stop 5 kilometers away from home and toward the zoo. The trip took 5 minutes.
She had to wait for the bus for 5 minutes.
Challenge • Make a ramp (books, wooden plank, ruler) • Roll the pencil (it’s Ms. Garris’s – keep it nice!) • Goal: make the pencil roll down the ramp and 30 centimeters beyond the ramp. No pushing!! No braking (stopping it)!
Ramp Challenge • Can you adjust to make it roll 30 centimeters? How? Describe your solution. • Can you adjust to make it roll 30 cm as fast as possible? How? Describe your solution. • Can you adjust to make it roll 30 cm as slowly as possible? How? Describe your solution.
Be careful! When measuring, make sure to use the actual scale on the ruler – not just the end of the ruler.
Speed vs. Velocity SPEED – tells you have fast or slow something is moving (changing position). Example = 25 km/h VELOCITY – tells you speed AND DIRECTION! (changing position in a certain direction) Example = 25 km/h EAST
What do you know about force? What do you need to know to describe a force? What happens if forces are both acting on the same thing? B I C it k L
Let’s try something • You have a rope – find the middle color. • Drape it across the desks to a table partner across from you. Write out the goal: GOAL = Each of you will need to pull on the rope in such a way as to make sure the middle it k does NOT move. L B CI EXPLAIN = How did you do it?
Let’s try again • Same scenario. • Drape it across the desks to a table partner across from you. Write out the GOAL: GOAL = Each of you will need to pull on the rope in such a way as to make sure the middle it k does move toward ONE of the pair. BL CI EXPLAIN = How did you do it?
What would you call that? • • If it doesn’t move? If it does move? Sketch an example of each onto your paper. Give two examples of balanced forces and two examples of unbalanced forces.
Introduction to FORCES
FORCES When you ride a bike, your foot PUSHES against the pedal. The push makes the wheels of the bike move. When you drop something, it is PULLED to the ground by gravity. A FORCE is a PUSH or PULL in a particular DIRECTION.
FORCES AFFECT HOW OBJECTS MOVE. Forces can affect motion in the following ways: They can make objects: BIG SCIENCE IDEA i) START MOVING ii) MOVE FASTER iii) MOVE SLOWER iv) STOP MOVING v) CHANGE DIRECTION vi) CHANGE SHAPE
FORCES Identify each picture as a PUSH or a PULL. Is the force causing a change in speed or direction or both?
FORCES Since forces cause changes in SPEED or DIRECTION of an object, we can say that forces change VELOCITY, so…. Forces cause ACCELERATION.
FORCES More than one force can act on an object at one time. What happens to the object when forces act depends on 2 things: 1) Strength of the Forces 2) Direction of the Forces
FORCES When 2 or more forces act on an object, the forces combine to form a net force. Forces may WORK TOGETHER or OPPOSE each other.
FORCES If the forces cancel each other out, and do not cause the object to move, the forces are said to be BALANCED. If the forces don’t cancel each other out – 1 force is stronger than the others – the forces are UNBALANCED and will cause a CHANGE IN MOTION.
MEASURING FORCE The strength of a force is measured in NEWTONS. The symbol is (N). We use a SPRING SCALE to measure force.
MEASURING FORCE - Always “zero” your balance before use. - Pull gently and with constant force. P O E! T S R HE -Practice using your spring scale to drag items across your desk.
Try on your own! • Take off a shoe (one per table) – keep your socks ON!! • Use the “mystery tool” to push or pull the shoe across the table. • Flip the shoe so that the laces are down and try again. • Write your observations!
Shoe lab Record the amount of force at the moment the shoe first moves! Record your data!
COMBINING FORCES Two forces in the same direction can add together to produce a larger net force. + = 5 N 5 N 10 N right
COMBINING FORCES Two forces in opposite directions can subtract to produce a smaller net force in the direction of the larger force. 5 N right = 10 N left 5 N left
COMBINING FORCES Two forces may cancel each other out (if equal and opposite) to produce NO NET FORCE. 5 N right = 5 N left 0 N (No Net Force)
Circle the best answer: 1) The forces shown above are PUSHING / PULLING forces. 2) The forces shown above are WORKING TOGETHER / OPPOSITE FORCES. 3) The forces shown above are EQUAL / NOT EQUAL. 4) The forces DO / DO NOT balance each other. 5) The net force is 1000 N TO THE RIGHT / 1000 N TO THE LEFT / ZERO. 6) There IS / IS NO motion.
Circle the best answer: 7) The forces shown are PULLING / PUSHING forces. 8) The forces shown are WORKING TOGETHER / OPPOSITE FORCES. 9) The forces shown are EQUAL / NOT EQUAL. 10) The forces DO / DO NOT balance each other. 11) The stronger force is pulling RIGHT / LEFT. 12) Motion is the to the RIGHT / LEFT.
50 N NET FORCE 200 N 150 N 13) Two movers are trying to move a heavy box. One mover pushes to the right with a force of 150 N. The other mover pushes to the left with a force of 200 N. a) Draw & label the forces on the diagram. b) What is the net force? 50 N LEFT c) Will the box move? YES d) If yes, in what direction? LEFT
14) Two movers are trying to move a heavy chair. One mover PULLS to the left with a force of 200 N. The other mover PUSHES to the left with a force of 200 N. a) Draw & label the forces on the diagram. 400 N NET FORCE b) What is the net force? 400 N LEFT c) Will the chair move? YES d) If yes, in what direction? LEFT 200 N
MIKE a) Draw & label the forces on the diagram. b) Is there a net force on the toy? YES = 10 N EAST 50 N 15) Four children are fighting over the same toy. Mike is pulling North with a 50 N force, Justin is pulling East with a 40 N force, Chantal is pulling South with a 50 N force, and Tykera is pulling West a 30 N force. TYKERA JUSTIN 40 N 30 N EAST d) Who gets the toy? 50 N c) In which direction will the toy move? JUSTIN 10 N Net Force CHANTAL
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