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The solutions are provided as handwritten PDF files.

During a bench press, does the amount of work, or power, required depend on the rate at which the weight is lifted?

Solution

A car has a mass of 1700 kg, a drag coefficient of 0.35, a rolling resistance coefficient of 0.01, a frontal area of 2 m

Solution

The cat righting reflex allows a cat to flip 180° from an upside down position, upon falling, so that it can land on its feet. By twisting a certain way, the cat can do this while maintaining zero angular momentum. To help understand how this is possible, consider the following physical system shown below, representing the cat. Relative to the shafts, the (identical) cylinders spin at an angular velocity

Solution

In a game of pool, calculate the trajectory of the cue ball after it strikes the object ball. The coefficient of kinetic friction between cue ball and table is

Solution

An inflated basketball has a mass of 0.624 kg and a radius of 0.119 m. Find the effective gravity acting on the basketball, given a density of air of 1.2 kg/m

Solution

Does the length of a skateboard affect the jumping distance over a ramp?

Solution

A heavy payload of mass 5000 kg needs to be pulled along a flat surface that has rollers on it. The speed of the payload as it is pulled is not to exceed 20 m/s. The payload is to increase in speed gradually as it is pulled, starting from rest. The pulling distance is 20 m. The plan is to use an engine or motor to rotate a heavy flywheel up to a certain rotational speed, and then disengage the engine/motor and use the rotating flywheel to pull the payload. Doing this avoids having to use a very powerful engine/motor, and instead allows the use of a much less powerful engine/motor to slowly add energy to an inertial system which will then have enough power to pull the payload. Design a flywheel system that can pull the payload as desired.

Solution

If someone can vertically jump a height

Solution

A bullet is fired out of a gun with a velocity of 300 m/s, with respect to ground. If the bullet has a mass of 0.06 kg and the gun has a mass of 1.5 kg, what percentage of the total kinetic energy (of the bullet and gun) does the bullet have?

Solution

The fully extended arm length of a shot putter is

It is given that the launch velocity

Use

Solution

A snowboarding half-pipe has an angle of inclination (pitch) of

Solution

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