Question

A car starting from a point travels towards east with a velocity of $36$ kmph. Another car starting from the same point travels towards north with a velocity of $24$ kmph. The magnitude of relative velocity of one with respect to another is

• A. $12\sqrt{13}$ kmph
• B. $30$ kmph
• C. $12$ kmph
• D. $20$ kmph

Answer 1

The correct option is A $12\sqrt{13}$ kmph

relative velocity =36i-24j
modulus of relative velocity= $\sqrt{144(9+4)}=12\sqrt{13}$ kmph
(because the relative velocities will be 24 and 36 in perpendicular directions)