Question

A person exerts a horizontal force of 42 N on the end of a door 96 cm wide. What is the magnitude of the torque if the force is exerted (a) perpendicular to the door and (b) at a 60.0° angle to the face of the door?

Answer 1

(a)
`\tau=40.32N\cdot m`

(b)
`\tau=34.92N\cdot m`

Step-by-step explanation:

Torque is the ability of a force to change the state of rotation of the body around an axis that passes through a given point. Therefore, it is defined as:

`\tau=Frsin\theta`

(a) In this case the angle between the force and the face of the door is
`90^\circ`:

`\tau=(42N)(96*10^(-2)m)sin90^\circ\\\tau=40.32N\cdot m`

(b)

`\tau=(42N)(96*10^(-2)m)sin60^\circ\\\tau=34.92N\cdot m`