A bus is moving on a straight road towards north with a uniform speed of $50 \mathrm{~km} /$ hour th

Question

A bus is moving on a straight road towards north with a uniform speed of $50 \mathrm{~km} /$ hour then it turns left through $90^{\circ}$. If the speed remains unchanged after turning, the increase in the velocity of bus in the turning process is\

Professor PC Thomas Classes · Answer

(a) : $\vec{v}_{1}=50 \mathrm{~km} / \mathrm{hr}$ due north\ $\vec{v}_{2}=50 \mathrm{~km} / \mathrm{hr}$ due west\ $-\vec{v}_{1}=50 \mathrm{~km} / \mathrm{hr}$ due south\ Magnitude of change in velocity\ $$ \begin{aligned} & =\left|\vec{v}_{2}-\vec{v}_{1}ight|=\left|\vec{v}_{2}+\left(-\vec{v}_{1}ight)ight|=\sqrt{v_{2}{ }^{2}+\left(-v_{1}ight)^{2}} \ & =\sqrt{(50)^{2}+(50)^{2}}=70.7 \mathrm{~km} / \mathrm{hr} \end{aligned} $$ $\vec{v}=70.7 \mathrm{~km} / \mathrm{hr}$ along south-west direction\