Mechanical Energy problems

At which point(s) on the roller coaster is the kinetic energy at its maximum?

• A
• B
• C
• D

At which point(s) on the roller coaster is the gravitational potential energy at its maximum?

• A
• B
• C
• D

As a pendulum swings from its highest to lowest position, what happens to its kinetic and potential energy? 

• The PE and KE increase and decrease together
• The PE decreases while the KE increases 
• Impossible to know without knowing the mass  

A 40 kg crate is picked up by a crane to a height of 50m. The crate falls. What is the velocity of the crate just before it hits the ground?

• 2000 Joules
• 19,600 Joules
• 19,600 m/s
• 31.3 m/s

When my velocity triples, my kinetic energy increases by ______ times.

• 9
•  3 
• 1.5
• 4.5

You drop a 5 kg ball from a height of 2 m. Just before it reaches the ground, what is the ball's velocity?

• 6.32 m/s
• 40 m/s
• 4.47 m/s
• 100 m/s

A 2 kg ball has an initial velocity of 6 m/s. How high up the ramp will it go?

• 1.8 m
• 10 m
• 6 m
• 12 m

A cliff diver with a mass of 125 kg jumps off a 50m high cliff, how fast will he be traveling just before he hits the water? (His height at this point is 0m)

(HINT: Find PE first. then KE = 1/2mv²

g = 9.8 m/s²

• 61,250 m/s

• 980 m/s

• 31.3 m/s

• 247.5 m/s

A person with a mass of 60 kg jumps in the air. If the gravitational potential energy is 1,470 J at the highest point, how did they jump?

• 3.2 m

• 49 m

• 24.5 m

• 2.5 m

A child and sled with a combined mass of 60.0 kg slide down a friction-less hill that is 8.00 m high. If the sled starts from rest, what is the speed at the bottom of the hill?

• 12.5 m/s

• 8.85 m/s

• 78.4 m/s

• 73.5 m/s