A particle of mass 120 g moving at speed of 750 cm/s is acted upon by a variable force opposite to
its direction of motion. If the velocity of the particle becomes 250 cm/s along the direction of force,
find the value of time 't' for which force acted.
1) 6sec
2) 9sec
3) 18sec
4)27sec
Answers & Comments
3) 18 sec not confirmed ans