Ap Physics Worksheet With Answers (Page 2 of 8) in pdf

Ap Physics Worksheet With Answers Page 2

15. A 25-N force pushes a 25 kg box 2.2 meters across a rough floor. The box is then lifted vertically and placed on a shelf that is 2.2

meters above the floor.

(a) How much total work is done on the box?

(b) How much energy is stored in the box when it is on the shelf?

= W

+ W

total

push

lift

= Fd + mgh

total

= (25 N)(2.2 m) + (25 kg)(9.8 N/kg)(2.2 m) = 544.5 J

total

Ep = (25 kg)(9.8 N/kg)(2.2 m) = 489.5 J

16. IF ABCD is a frictionless track, what is the speed of the object on section CD? Use an energy bar chart in your response.

ΔEp = ΔEk

MgΔh = ½ MΔv

Δv = √(2gΔh) = √(2)(9.8 N/kg)(0.35 m) = 2.62 m/s

17. What is the speed of the pendulum shown at the bottom of its swing? Use an energy bar chart in your response.

ΔEp = ΔEk

MgΔh = ½ MΔv

Δv = √(2gΔh) = √(2)(9.8 N/kg)(0.20 m) = 1.98 m/s

18. A ball of mass 2.00-kg is dropped from a height of 1.5 m (from the ground) onto a massless spring (the spring has an equilibrium

length of 0.50 m). The ball compresses the spring by an amount of 0.20 m by the time it comes to a stop. Calculate the spring

constant of the spring, k.

Ap Physics Worksheet With Answers Page 2