Question

 A wrench is used to tighten a nut. A 15N perpendicular force is applied 50cm away from the axis of rotation, and moves a distance of 10 cm as it turns. What is the torque applied to the wrench?​

Answer 1

Given:

• Wrench is used to give 15 N force at a distance of 50 cm from axis of rotation.

To find:

• Torque applied bg wrench ?

Calculation:

• Torque (denoted by letter Tau- $\tau$) is the rotational analogue of force.

• In other words, torque is a vector quantity denoting the moment of force , or the vector product between displacement vector (from axis) and force vector

In simple terms , we can say :

$\vec{ \tau }= \vec{r} \times \vec{F}$

$\implies | \vec{ \tau }| = r \times F \times \sin( {90}^{ \circ} )$

$\implies | \vec{ \tau }| = r \times F$

• Putting values in SI UNITS:

$\implies | \vec{ \tau }| = 0.5 \times 15$

$\implies | \vec{ \tau }| = 7.5 \: Nm$

So, torque applied by wrench is 7.5 Nm.