Question

A block of mass 5 kg, as shown in the figure, does not move on applying the force F. The frictional force acting on the block is ​

Answer 1

Answer:

Coefficient of friction, μ=0.2

Mass of block, M=5kg

Friction force, F

r

​

=μ(mg+Fsin45)=0.2×(5×9.8+

2

​

20

​

)=12.63 N

Net force, F

net

​

=Fcos45−F

r

​

=

2

​

20

​

−12.63=1.5 N

Acceleration, a=

m

F

net

​

​

=

5

1.5

​

=0.3 ms

−2

Apply kinematic equation of motion

V=U+at=0+

5

1.5

​

×15=4.5 ms

−1

Final velocity is 4.5 ms

−1

 

Explanation: