1.Easy
A 1 kg ball is dropped from rest from a height of 16 m. Ignore air resistance. Find its speed v just before it hits the ground.
m = 1 kgh = 16 mg = 9.81 m/s²
v = m/s
Work & energy worksheet with answers
2.Easy
A 5 kg block slides at 5 m/s on a smooth horizontal surface into a spring of stiffness 500 N/m. Find the maximum compression x of the spring, in cm.
m = 5 kgv = 5 m/sk = 500 N/m
x = cm
3.Medium
A toy launcher has a vertical spring of stiffness 1500 N/m. A 0.05 kg ball is placed on it and the spring is compressed by 8 cm, then released. Ignoring air resistance and the spring’s mass, find the height h the ball rises, measured from its position when the spring was compressed.
m = 0.05 kgk = 1500 N/mx = 8 cmg = 9.81 m/s²
h = m
4.Medium
A block slides from rest down a slope at 35° to the horizontal. The coefficient of kinetic friction is 0.4. Find its speed v after it has slid 19 m along the slope.
θ = 35°μ = 0.4d = 19 mg = 9.81 m/s²
v = m/s
5.Hard
A 1 kg cart is released from rest at a height of 16 m on a smooth track that leads into a vertical circular loop of radius 4 m. Find the speed v of the cart at the top of the loop.
m = 1 kgh = 16 mR = 4 mg = 9.81 m/s²
v = m/s
6.Hard
A 4 kg block is released from rest at height 3 m on a smooth ramp. At the bottom it crosses a rough horizontal strip 4 m long (μ = 0.1) and then runs onto a spring (k = 5000 N/m) on a smooth surface. Find the maximum compression x of the spring.
m = 4 kgh = 3 mL = 4 mμ = 0.1k = 5000 N/mg = 9.81 m/s²
x = cm
Answer key
- 1. v = 17.72 m/s
- 2. x = 50 cm
- 3. h = 9.786 m
- 4. v = 9.575 m/s
- 5. v = 12.53 m/s
- 6. x = 20.2 cm
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