A 10 kg block is pulled along a rough floor by a horizontal force of 30 N. Friction is 10 N. What is the block's acceleration?
Answer and explanation
Correct answer: C. 2 m/s^2
- Step 1: Net force = 30 - 10 = 20 N.
- Step 2: a = F_net / m = 20 / 10 = 2 m/s^2.
Answer
2 m/s^2.
Why not the others: Acceleration depends on the net force; ignoring friction, adding it, or using friction alone gives the other values.
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