Question

An engine can pull 4 coaches at a maximum speed of 20 m/s. Mass of the engine is twice the mass of
every coach. Assuming resistive forces to be proportional to the weight, approximate maximum speeds of
the engine when it pulls 12 and 6 coaches are :​

Answer 1

Answer:

The answer is v=15m/s

Explanation:

P=k 6mgv----------------(1)

P=k 14mgv1----------------(2)

From eqn 1 and 2:-

 

6mgv=14mgv1

6v=14v1

V1=6×20/14

V1=8.5m/s

Also,

6mgv=8mgv2

6v=8v2

V2=6×20/8

V2=15m/s