Which force can possibly act on a body moving in a straight line?
a) Tangential force
b) Friction force
c) Centrifugal force
d) Centripetal force

Answer

A, B, C, D

Explanation

a. `m=2kg, theta=37^0 F=20N`
From the free body diagram
`F=(2gsintheta)+ma`
`rarr a=(20-20sintheta)/2=4m/sec^2`
`s=ut+1/2at^2=2m`
`(u=0, t=1s, a=1.66)`
So,workdone `W=FS=20xx2=40J`

b. If W=40J
`S=W/F=40/20=2m`
So, work done `W=-mgh`
`=020xx1.5=-24J`
c. `v=u+at`
`=4xx1=4m/sec`
So, `K.E. =1/2mv^2`
`=1/22xx16=6J`