The mass moment of inertia (mmi) of a flywheel (large disc) attached to the main (c) shaft of a rock crushing machine the machine maintain a continuous crushing force. the designer of the machine has determined that a mmi of 100 kg. m2 is required. the fly wheel is to be made of cast iron with a density of 7210 kg/m2. if the thickness (axial length) of the flywheel is limited to 0.25 m, what is the minimum flywheel radius needed to provide the required mmi? a symbolic solution is required initially. work in base si units state the units for your answer.

Imagine you are riding on a yacht in the ocean and traveling at 20 mph. you then hit a golf ball at 100 mph from the deck of the yacht. you see the ball move away from you at 100mph, while a person standing on a near by beach would observe your golf ball traveling at 120 mph (20 mph + 100 mph). now imagine you are aboard the hermes spacecraft traveling at 0.1c (1/10 the speed of light) past mars and shine a laser from the front of the ship. you would see the light traveling at c (the speed of light) away from your ship. according to einstein’s special relativity, how fast will a person on mars observe the light to be traveling? a) 0.1c (1/10 the speed of light) b) c (the speed of light) c)1.1c (c+0.1c)