Equilibrium

Question 1

Torque

Answer 1

• The rotary effect of a force about an axis of rotation

- Product of the force and the perpendicular distance between the force’s line of action and the axis

Question 2

Other names for torque

Answer 2

• Moment of force

- Rotary force

Question 3

Other names for perpendicular distance

Answer 3

• Moment arm

- Force arm

Question 4

Force Couple

Answer 4

A pair of equal, oppositely directed forces that act on opposite sides of an axis of rotation to produce torque

Question 5

Net/Resultant Torque

Answer 5

The final torque that results from combining 2+ torques which determines the magnitude and direction of the movement

Question 6

Lever

Answer 6

A simple machine consisting of a relatively rigid, bar-like body that may be made to rotate about an axis

Question 7

Fulcrum

Answer 7

The point of support, or axis, about which a lever may be made to rotate about an axis

Question 8

First Class Lever

Answer 8

• The fulcrum is between the force arm and resistance arm

- Examples: see-saw, pliers, crowbar

Question 9

Second Class Lever

Answer 9

• The resistance arm is between the fulcrum and the force arm
• Examples: wheelbarrow, opening/closing a door

Question 10

Third Class Lever

Answer 10

• The force arm is between the fulcrum and the resistance arm
• Examples: swinging a bat, shoveling (where the front hand lifts and back hand is axis)

Question 11

Mechanical Advantage

Answer 11

• Ratio of force arm to resistance arm for a given lever

- MA = Force Moment Arm/Resistance Moment Arm