Question

Two parallel rail tracks run north-south. Train A moves north with a speed of 54 km/h and train B moves south with a speed of 90 km/h. What is the relative velocity in m/s of (a) B with respect to A
(b) the ground with respect to B
(c) A monkey running on roof of train A (with velocity 5m/s with respect to A) as observed by a man standing on the ground​

Answer 1

Explanation:

I solved it in my attachment

Answer 2

Answer:

a.

v

BA

=

v

B

-

v

A

Hence, velocity of train B w.r.t train A is 144 km/h toward south.

b. Velocity of ground w.r.t. B

v

g,B

=v

g

−v

B

= 0 - 90$$

v

g,B

= -90 km/h

Hence, velocity of ground w.r.t train B is 90 km/h towards north.

c.

v

m,g

= v m,A + v Ag

= 18 - 54 = -36 km/h

Hence, velocity of monkey will be 36 km/h toward north.