Exam 5: Special Topics

A mountain biker performs a 110 m climb up a mountain trail and, in doing so, completes 82000 Joules of work. Given what is known about this performance, what is the cyclist's mass?

The coefficient of restitution will be lowest for:

The centre of percussion point on a bat or racket has important implications for performance

Which of the Laws of Physics is the elastic region of a stress vs strain curve an example of?

During a game of billiards, a player propels the smooth white ball with a mass of 0.2 kg into the smooth wall surrounding the edge of the table. The ball collides with the wall at an angle of 35° and is travelling at a velocity of 3.5 m/s at the point of impact. If the coefficient of restitution is 0.65, determine the magnitude and direction of the ball's vertical velocity after its collision with the wall (i.e. v'y). Note: As both the ball and wall are smooth, assume that the horizontal component of the ball's velocity is unchanged after the collision (i.e. v'x); although it's direction will be opposite.

When would it be good to use the dead zone in hitting a ball in tennis?

What is the strain experienced if a 0.5 m bone is shortened to 0.498 m during compression loading?

A typical value for the term (1+e) when kicking a soccer ball is 1.5

In the human body, the conversion of energy from chemical to mechanical energy is imperfect, meaning that the amount of chemical energy (e.g. adenosine triphosphate) is greater than the mechanical energy involved in producing a movement. Using the law of conservation of energy, briefly explain where the rest of the chemical energy goes.

An accomplished high-jumper is recorded as having a vertical take-off velocity of 6.12 m/s. In the absence of any significant external forces, how high would the athlete have jumped?

A 70 kg cyclist who rides up a 60 m long hill in 1 minutes 45 seconds produces a greater average power than an 85 kg cyclist who ascends the same hill in 2 minutes 3 seconds? Assume that the two cyclists are riding bicycles of equivalent mass.

Stress is measured in N/m² and strain is represented as a proportion

If an athlete displaces a 20 kg kettle bell vertically by 70 cm, how much work has he done?

Stress is measured in N·m^-2 and strain is dimensionless

If the mountain biker produced an average power of 285 Watts during the 110 m, how long, in minutes and seconds, did it take him to complete the climb?

A head-on collision is an example of a central impact

Which of the following type of loading causes a material to shorten?

Describe the term "sweet spot" that is commonly used in the sporting media/literature

What is 3,000,000 Pa expressed in Mega (M) Pa?

Provide a brief of the differences between positive and negative work.