A block rests on a fixed rough inclined plane and a horizontal force F is applied to it, as shown in the figure. Which of the following statements are correct? (1) Normal reaction on the block is F si

Question

A block rests on a fixed rough inclined plane and a horizontal force $F$ is applied to it, as shown in the figure. Which of the following statements are correct?

(1) Normal reaction on the block is $F \sin θ + m g \cos θ$

(2) The frictional force is zero when $F \cos θ = m g \sin θ$

(3) The value of limiting friction is $μ (m g \sin θ + F \cos θ)$

(4) The value of limiting friction is $μ (m g \sin θ - F \cos θ)$

TestHub · Accepted Answer

As the object is at rest, therefore from FBD,

Normal Reaction $N = m g \cos θ + F \sin θ$ .....(i)

Limiting Friction $f_{L} = μ N = μ (m g \cos θ + F \sin θ)$ ......(ii)

Also, if $m g \sin θ = F \cos θ$

then the object has no tendency of motion; hence friction is zero in this case.

Physics - NLM Question with Solution | TestHub

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