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## Homework Statement

A gate to a bullpen is open at a right angle to the fence and the bull is rushing toward the opening to get out. The farmer estimates that the bull will reach the opening in 3 sec. so he pushes at the end of the gate (always at a right angle) with a force of 100N. The moment of inertia of the gate about the hinge is 1,000 kg m^2 and the gate length is 3.

a. What is the magnitude of the torque applied by the farmer.

b. What is the rotational kinetic energy of the gate after 3 seconds

c. Through what angle will the gate have rotated after 3 sec.

d. Will the gate be closed.

## Homework Equations

Torque, KE roational, Angular Kinematics

## The Attempt at a Solution

a. Torque= rFsin(theata) = (3)(100)sin90= 300Nm

b. KE= (1/2)(I)(w^2) = (1/2)(1000)(?)

c. angle= at^2/2?

d. ?