A constant force of N acts for s on a kg ball initially at rest. What is the ball's final speed?
Answer and explanation
Correct answer: B. 20 m/s
- Step 1: Impulse N s. Step 2. Impulse , so and . Answer: 20 m/s. Why not the others: 10 is the impulse in N s, not the speed; 5 m/s multiplies by the mass instead of dividing; 250 divides the force by the time.
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