Q. A moving car possesses average velocities of 5ms^{-1}, 10ms^{-1} and 15 ms^{-1} in the first, second, and third seconds respectively. What is the total distance covered by the car in these 3s ?

(a) 15m

(b) 30m

(c) 55m

(d) 45m

Ans: (b)

Sol:

$ \displaystyle S = v_1 t_1 + v_2 t_2 + v_3 t_3 $

$ \displaystyle = 5\times 1 + 10 \times 1 + 15 \times 1 $

= 30 m