Answer to Question #138285 in Mechanics | Relativity for Parvinder singh

Question

Find the distance and time at which a fast moving train B will excell the train A. Where they are moving in the same direction with velocity 50 km/hr for A and 80 km/hr for B. Where train A has initial displacement of 1200 km & train B has no initial displacement

Answer 1

solution

velocity of train A(v_a)=50km/hr

velocity of train B(v_b)=80km/hr

displacement of train A(s_a)=1200 km

velocity of train B with respect to train A(v_ba) =v_b - v_a

v_ba =80 - 50=30km/hr

time taken by train B to over take the train A(t)=$\frac{s_a}{v_{ba}}=\frac{1200}{30}=40hr$

distance travel by train B in 40hr (s_b) =$v_bt$

$s_b=80\times40=3200km$

so times taken by train B to excell train A is 40hr and distance travel by train B is 3200km.