The kinetic energy of a particle continuously increases with time. Then

Options

A. the resultant force on the particle must be parallel to the velocity at all instants.
B. the resultant force on the particle must be at an angle less than `90^(@)` with the velocity all the time
C. its height above the ground level must continuously decreases
D. the magnitude of its linear momentum is decreasing continuously

Answer

B

Explanation

`dW_(F)=vec(F).vec(ds)=dk gt 0rArr |vec(F)||vec(ds)|cos theta gt 0`
`rArr 0 lt theta lt 90^(@)`
`p=sqrt(2m(KE)), KE uarr ` so `p uarr`.