Newton’s laws of motion

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Slide 1

This lecture will help you understand:

Newton’s First Law of Motion

Newton’s Second Law of Motion

Forces and Interactions

Newton’s Third Law of Motion

Summary of Newton’s Three Laws

Slide 2

Newton’s First Law of Motion

The law of inertia: (originating with Galileo)

Every object continues in a state of rest or of uniform speed in a straight line unless acted on by a nonzero force.

Slide 3

A sheet of paper can be quickly withdrawn from under a soft-drink can without the can toppling, because

A. gravity pulls harder on the can than on the paper.

the can has weight.

the can has inertia.

None of the above.

Newton’s First Law of Motion

CHECK YOUR NEIGHBOR

Slide 4

A sheet of paper can be quickly withdrawn from under a soft-drink can without the can toppling, because

A. gravity pulls harder on the can than on the paper.

the can has weight.

the can has inertia.

None of the above.

Newton’s First Law of Motion

CHECK YOUR ANSWER

Slide 5

If you swing a stone overhead in a horizontal circle and the string breaks, the tendency of the stone is to follow a

A. curved path.

straight-line path.

spiral path.

vertical path.

Newton’s First Law of Motion

CHECK YOUR NEIGHBOR

Slide 6

If you swing a stone overhead in a horizontal circle and the string breaks, the tendency of the stone is to follow a

A. curved path.

straight-line path.

spiral path.

vertical path.

Newton’s First Law of Motion

CHECK YOUR ANSWER

Slide 7

Examples of Inertia

Slide 8

Inertia in Action

Rapid deceleration is sensed by the driver who lurches forward.

It is also an example of Newton’s Second Law because no force stops the driver while the brakes stop the vehicle.

Slide 9

Inertia in Action

When you flip a coin in a high-speed airplane, it behaves as if the airplane were at rest.

The coin keeps up with you.

Slide 10

Inertia in Action

Can the bird drop down and catch the worm if the Earth moves at 30 km/s?