A wooden box is placed on the horizontal ground. The gravity of the box is 4000N. Under the horizontal thrust of 2000N, the box moves forward at a speed of 0.5mgs for 10s (1) How far does the box go? (2) What is the work done by the thrust on the box in these 10 seconds?
(1)s=vt=0.5m/s * 10s=5m;
(2)w=fs=2000N * 5m=10000J;
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