Homework Help: Newtons First Law Question

1. Feb 11, 2012

shahmeer

The problem statement, all variables and given/known data

Which situations below are examples of Newton's First Law?

a) Your herd jerking back when car accelerates rapidly.
b) Hitting shoe on wall to knock off snow.
c) An apple hanging motionless on a tree.
d) All of the above

I know newton's first law states that objects in motion stay in motion and objects at rest tend to stay at rest; the law essentially describes inertia.

The only situation I am absolutely sure about is a but according to the answer key the answer is d. I guess b could work, the shoe stops but snow keeps moving but I am not sure.

Any clarification would help me greatly. Thanks.

2. Feb 11, 2012

Millacol88

Yes, "d" would be the correct response. Your head tends to want to continue in its current state of motion, so you percieve it being jerked back when the car accelerates. Your right about the shoe with the snow. And the apple hanging in the tree has essentially no "push or pull" or outside influences on it so wit will maintain its state of motion (in this case staying still).

That clear things up?

3. Feb 11, 2012

shahmeer

Yes, thank you

4. Feb 11, 2012

PhanthomJay

Note the comment above in red.