Kinesiology CH. 3 Quiz

Which of the following could be done to reduce the amount of force needed to move a lever?

-move resistance closer to axis -apply force further away from the axis giving you longer lever arm -decrease resistance by taking away ALL THE ABOVE

Identify Newton's law of acceleration

A change in the acceleration of a body occurs in the dame direction as the force that caused it

Which of the following statements accurately represents the relationship between linear and angular motion?

Angular motion of joints produces the linear motion of walking

What are the three components of a lever system?

Axis, force arm, and resistance arm

Assuming that the bat speed and pitched ball velocity were the same, the bs,l hit with the middle of the bat would travel further than the ball hit with the larger end of the bat. T/F

False

In rapid running movements in which moving inertia is high, an individual has to raise the body's center of gravity to maintain balance when stopping or changing direction. T/F

False

In the context of wheels and axels, only the radius of the wheel corresponds to the force arms. T/F

False

A ____ lever system is arranged like a pendulum, with the axis positioned between the force and resistance arms

First-class

Mass is the effect of gravity on the amount of matter in the body. T/F

Flase

Identify Newton's law of reaction

For every action there is an opposite and equal reaction

Kinematics is concerned with the description of motion and includes consideration of each of the following except:

Force

A _____ lever system is arranged with the resistance arm between the axis and force arm

Second-class

When running or jumping, plantar flexion occurs at the ankle joint so that athletes can apply force to the ground through the base of their toes. The base of the toes pivot on the surface (axis), and the muscles that attach to the heel are working against the weight of the athlete. This is similar to a wheelbarrow, where the resistance being moved is between the axis (fulcrum) and the force arm. What type of lever system is this?

Second-class lever system

Which characteristics best explains why athletes with shorter limbs have an advantage in activities such powerlifting and gymnastics?

These athletes have greater mechanical advantage because of smaller resistance arms; they require smaller muscle forces and joint torques to work against resistance.

A resistance arm is defined as the distance between an axis and the point of resistance application. T/F

True

Short force arms and long resistance arms require great muscular strength to produce movement. T/F

True

The predominant lever in the human body is the third-class lever. T/F

True

Newton's law of inertia states that

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