Initially car $A$ is 10.5 m ahead of car $B$. Both start moving at time $t=0$ in the same direction

Question

Initially car $A$ is 10.5 m ahead of car $B$. Both start moving at time $t=0$ in the same direction along a straight line. The velocitytime graph of two cars is shown in figure. The time when the car $B$ will catch the car $A$, will be

Professor PC Thomas Classes · Answer

(a) : Let the cars meet at $C$.\ For car $A: x=v_A t ; x=10 t$\ Acceleration of car $B: a_B=	an 45^{\circ}=1 \mathrm{~m} / \mathrm{s}^2$\ For car $B: x+10.5=\frac{1}{2} 1 t^2$ \ $ \Rightarrow 10 t+10.5=\frac{1}{2} 1 t^2 \Rightarrow t^2-20 t-21=0 ; t=21 \mathrm{~s} $