A bicycle rider has a speed of 20.0 m/s at a height of 60 m above sea level when he begins coasting down hill. Sea level is the zero level for measuring gravitational potential energy. Ignoring friction and air resistance, what is the rider's speed when he coasts to a height of 18 m above sea level?

Astone dropped into a well is heard to strike the water after 8seconds. find the depth of the well if the velocity of sound is 350m/s

Amarble, a bowling ball, a basketball, and a baseball are rolling across the floor at 10 m/s. which one has the greatest kinetic energy? the marble the bowling ball the basketball the baseball

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)