# Laws of Motion

## Question 1

A120 lb person is being lifted aloft by a rocket which accelerates uniformly to an upward speed of 300 ft/sec in 2 sec. What is the upward acceleration in multiples of g?

Hint 1

## Question 2

A120 lb person is being lifted aloft by a rocket which accelerates uniformly to an upward speed of 300 ft/sec in 2 sec.  What is the apparent weight of the person during acceleration?

Free body diagram: N - Normal reaction which is equal to the apparent weight of the man.

Hint 2

## Question 3

A short 10 gram string is used to pull a 50 gram toy across a frictionless horizontal surface. If a 3.0 x 10 Newton force is applied horizontally to the free end. Find the force of the string on the toy, at the other end.

Hint 3

## Question 4

A rocket exhausts fuel with a velocity of 1500 m/s, relative to the rocket. It starts from rest in outer space with fuel comprising 80% of the total mass. Find its speed when all the fuel has been exhausted.

Hint 4

## Question 5

A 640 N acrobat falls 5.0 m from rest into a net. The net tosses him back up with the same speed he had just before he hit the net. Find the average force exerted on him by the net during this collision.

Hint 5