2. A person exerts a perpendicular force of 75 N on a door. Calculate the torque on the door hinges if the force is applied a distance of 30 cm, 50 cm, and 75 cm from the hinge.

To calculate the torque on the door hinges, you need to multiply the force applied perpendicular to the door by the distance from the hinge. The formula for torque is:

Torque = Force x Distance

Given:
Force (F) = 75 N
Distance from the hinge (d) = 30 cm, 50 cm, and 75 cm

First, we need to convert the distance from centimeters to meters. There are 100 centimeters in 1 meter, so:

Distance (in meters) = Distance in centimeters / 100

Now we can calculate the torque for each distance:

For 30 cm:
Torque = 75 N x (30 cm / 100) m
= 75 N x 0.30 m
= 22.5 Nm

For 50 cm:
Torque = 75 N x (50 cm / 100) m
= 75 N x 0.50 m
= 37.5 Nm

For 75 cm:
Torque = 75 N x (75 cm / 100) m
= 75 N x 0.75 m
= 56.25 Nm

Therefore, the torque on the door hinges when the force is applied at a distance of 30 cm, 50 cm, and 75 cm from the hinge is 22.5 Nm, 37.5 Nm, and 56.25 Nm respectively.