OCT414 Topic 4 - Biomechanic Principles II

What is torque?

• The tendency of a force to rotate an object

• The resistance to motion between two surfaces

• The rate of change of velocity

• The force that opposes the motion of an object

What is the force arm in a lever system?

• The perpendicular distance between the location of force application and the axis of rotation

• The distance between the axis and the point of resistance application

• The shortest distance from the axis of rotation to the line of action of the force

• The greater the distance of the force arm, the more torque produced by the force

What is the mechanical advantage of a wheel and axle?

• Radius of wheel / Radius of axle

• Radius of axle / Radius of wheel

• Force arm / Moment arm

• Moment arm / Force arm

What is the purpose of a pulley?

• To change the direction of force

• To increase the amount of force applied

• To decrease the amount of mechanical energy needed

• All of the above

What is the law of inertia?

• A body in motion tends to remain in motion at the same speed in a straight line unless acted on by a force

• A change in acceleration is directly proportional to the force causing it and inversely proportional to the mass of the body

• For every action, there is an opposite and equal reaction

• The resistance to motion between two surfaces

What is the difference between static friction and kinetic friction?

• Static friction occurs between two objects that have not yet begun to move, while kinetic friction occurs between two objects that are sliding upon one another

• Static friction is always greater than kinetic friction

• Static friction depends on the hardness and roughness of the surface textures

• All of the above

What is rolling friction?

• Resistance to an object rolling across a surface

• Resistance to motion between two surfaces

• The rate of change of velocity

• The force that opposes the motion of an object

What is the relationship between force and acceleration?

• Force is directly proportional to acceleration

• Force is inversely proportional to acceleration

• Force has no effect on acceleration

• Force and acceleration are unrelated

What is the purpose of the law of reaction?

• To explain the relationship between force and acceleration

• To describe the resistance to motion between two surfaces

• To determine the mechanical advantage of a lever system

• To explain the equal and opposite reaction to an action force

What is the definition of displacement?

• The actual sum length of measurement traveled

• The distance that an object moves in a specific amount of time

• The resistance to motion between two surfaces

• The change in location of a rotating body