question_answer

A particle is moving eastwards with a velocity of 5 m/s. hi 10 seconds the velocity changes to 5 m/s northwards. The average acceleration in this time is

A) \[\frac{1}{2}m{{s}^{-2}}\] North

B) \[\frac{1}{\sqrt{2}}m{{s}^{-2}}\] North - East

C) \[\frac{1}{\sqrt{2}}m{{s}^{-2}}\] North-West

D) zero

Correct Answer: C

Solution :

[c] \[|\overline{{{V}_{2}}}-\overline{{{V}_{1}}}|\,=\sqrt{{{5}^{2}}+{{5}^{2}}}=5\sqrt{2}\] \[a=\frac{5\sqrt{2}}{10}=\frac{1}{\sqrt{2}}m/{{s}^{2}}\,N-W\]