THE PRACTICE STUDIO
Go slowly. Ask why. Make it yours.
PRACTICE / Inelastic collisions
Momentum survives the collision. Does kinetic energy?
A 2 kg trolley moves right at 6 m/s. A 1 kg trolley moves left at 3 m/s. They collide and lock together on a level rail.
How much kinetic energy is lost in the collision?
Organize the givens & assumptions
- m1 = 2 kg, u1 = +6 m/s
- m2 = 1 kg, u2 = −3 m/s
- Combined mass: 3 kg
The net external horizontal impulse during collision is negligible. The trolleys stick and do not rotate. Choose right as positive.
- A
- B
- C
- D
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