Question

The force acting on a pendulum to bring it to its perpendicular resting point is called the restoring force. the restoring force f, in newtons, acting on a string pendulum is given by the formula f = mg sinθ where m is the mass in kilograms of the pendulum's bob, g ≈ 9.8 meters per second per second is the acceleration due to gravity, and θ is angle at which the pendulum is displaced from the perpendicular. what is the value of the restoring force when m = 0.6 kilogram and θ = 45°? if necessary, round the answer to the nearest tenth of a newton.

Answer 1

Restoring force $=mg sin \Theta$

Given,  $m=0.6 kg$ , $g= 9.0m/s^{2}$ and $\Theta = 45^{0}$

Substituting these value in above formula we get,

$F= 0.6 \times 9.8 \times sin  45^{0} N$

$F= 5.88 \times sin\frac{1}{\sqrt{2} }$

$F= 4.15 N$$\simeq  4.2 N$

Therefore, the value of restoring force is 4.2 N.