1. A 70-kg box is slid along the floor by a 400-N. The coefficient of friction between the box and the floor is 0.50 when the box is sliding. Find the acceleration of the box.

2. An 8000-kg engine pulls a 40,000 kg train along a level track and gives it an acceleration a1 = 1.20 m/s . What acceleration (a2) would the engine give to a 16,000-kg train?

Question

1.	A 70-kg box is slid along the floor by a 400-N. The coefficient of friction between the box and the floor is 0.50 when the box is sliding. Find the acceleration of the box. 


2.	An 8000-kg engine pulls a 40,000 kg train along a level track and gives it an acceleration a1 = 1.20 m/s . What acceleration (a2) would the engine give to a 16,000-kg train?

jiteshmeghwal9 · Answer

When the box is sliding frictional force acting on it is $$\mu_k N$$

jiteshmeghwal9 · Answer

So 
400- $\mu_kN$=ma

jiteshmeghwal9 · Answer

Force that engine can apply = (40000*1.20) N

Acceleration given to 16000 kg train = $$\frac{40000*1.20}{16000}$$

jiteshmeghwal9 · Answer

|dw:1475735451665:dw|