A stone is projected with speed `20 m//s` at angle `37^(@)` with the horizontal and it hits the ground with speed `12m//s` due to air resistance. Assume the effect of air resistance to reduce only horizontal component of velocity. Then the time of flight will be-

Options

A. greater than `2.4 sec`
B. less than `2.4 sec`
C. `2.4 sec`
D. depends on other data

Answer

C

Explanation

Time of flight only depends on the vertical component of the velocity. Hence, `T=(2 u sin theta)/g=2.4 s`