Question

Two trains T₁ and T₂ are running on two parallel tracks. Train T₁ moves with a speed of 40 kmh^-1 due east and train T₂ moves with a speed of 60 kmh^-1 due west. Calculate (i) the speed of train T₁ with respect to the T₁ (ii) the speed of train T₂ with respect to the train T₁ and (iii) the speed of ground with respect to the train T₁.

Answer 1

Consider the direction as positive towards East and negative towards West.

= + 40 - (-60) = 100 kmh^-1.

Thus, train T₁ appears to run with a speed of 100 kmh^-1 due east with respect to the train T₂.

Thus, the train T₂ appears to run with speed of 100 kmh^-1 due west w.r.t., train T₁.

(iii) Speed of ground with respect to train T₁.

v_g T₁ = v_g - v_T1 = 0 - 40 = -40 kmh^-1.

Thus, the ground appears to move with a speed of 40 kh^-1 due west w.r.t the train T₁.