Question

A particle moves from point (5, 9, 7) to (8, 5, 2) with constant speed 10√2m/s on a straight line A force F(1)=(3 icap +4 jcap)N is acting on particle throughout is journey. Choose correct statement.

a. velocity vector of the particle is (6icap-8jcap-10kcap)m/s
b. work done by the given force in journey is 7J
c. Power delivered by given force at any time is -14W
d. There must be some other force acting on the particle. ​

Answer 1

Answer:

(d)

Explanation:

it is mentioned that the object displaces with a constant velocity, hence it's kinetic energy is not changed, there must be some other force to stop the object from accelerating under the influence of a present force. work done by given force is -7J so the work done by the unknown force must be 7 joules.