ACCELERATE D MOTION NEWTONS SECOND LAW OF MOTION

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ACCELERATE D MOTION

ACCELERATE D MOTION

NEWTON’S SECOND LAW OF MOTION • States the relationship between: – mass – force

NEWTON’S SECOND LAW OF MOTION • States the relationship between: – mass – force – acceleration

A net force acting on an object; • causes the object to accelerate •

A net force acting on an object; • causes the object to accelerate • in the same direction of the force

The amount of acceleration is determined by 2 things!

The amount of acceleration is determined by 2 things!

1. ) the size of the force • larger force causes greater acceleration –

1. ) the size of the force • larger force causes greater acceleration – (force is directly proportional to acceleration)

2. ) the mass of the object • larger mass results in less acceleration

2. ) the mass of the object • larger mass results in less acceleration – (mass is inversely proportional to acceleration)

NEWTON’S 2 nd law Equation • force = mass x acceleration F = ma

NEWTON’S 2 nd law Equation • force = mass x acceleration F = ma

UNITS of FORCE

UNITS of FORCE

Mass • is measured in kilograms (kg)

Mass • is measured in kilograms (kg)

Acceleration • is measured in meters per second per 2 second (m/s )

Acceleration • is measured in meters per second per 2 second (m/s )

Force • is measured in Newtons (N)

Force • is measured in Newtons (N)

Knowing that…. . • force = mass x acceleration *THEN* • 1 Newton must

Knowing that…. . • force = mass x acceleration *THEN* • 1 Newton must equal 1 kg • m/s 2

If you drop a bowling ball and a marble from a bridge at the

If you drop a bowling ball and a marble from a bridge at the same time which will hit the ground first?

The bowling ball and the marble will hit the ground; • at the same

The bowling ball and the marble will hit the ground; • at the same time • Why?

Even though the bowling ball has more mass than the marble, • it also

Even though the bowling ball has more mass than the marble, • it also has more inertia (resistance to a force)

Acceleration caused by Earth’s gravity. 2 (g) = 9. 8 m/s

Acceleration caused by Earth’s gravity. 2 (g) = 9. 8 m/s

Objects that are pushed or thrown downward • are accelerated by two forces: 1.

Objects that are pushed or thrown downward • are accelerated by two forces: 1. ) the force of gravity 2. ) the force of the “push or throw”

Objects that are pushed or thrown downward • have an acceleration greater than 9.

Objects that are pushed or thrown downward • have an acceleration greater than 9. 8 m/s 2

Since Freely Falling objects dropped at the same time should reach the ground at

Since Freely Falling objects dropped at the same time should reach the ground at the same time…. .

Why does a penny dropped at the same time as a feather, land on

Why does a penny dropped at the same time as a feather, land on the ground first?

Air Resistance: • force that air exerts on all moving objects • goes against

Air Resistance: • force that air exerts on all moving objects • goes against an object’s motion car’s motion air resistance

As gravity pulls an object down; • Air resistance pushes up

As gravity pulls an object down; • Air resistance pushes up

Air Resistance depends upon 3 things. 1. ) velocity 2. ) shape 3. )

Air Resistance depends upon 3 things. 1. ) velocity 2. ) shape 3. ) density

The longer an object is allowed to fall; • the air resistance increases upward

The longer an object is allowed to fall; • the air resistance increases upward

Terminal Velocity • Highest velocity that will be reached by a falling object

Terminal Velocity • Highest velocity that will be reached by a falling object