Ablock of copper (c = 390 j/kg°c) is heated from 20.0 c to 60.0 c. how much heat (in j) is absorbed by the copper if its mass is 45.0 g?

Gasoline comes from petroleum, which is made from ancient living things. petroleum, therefore, contains a type of energy. a. heat b. nuclear c. biological d. chemical potential

Two masses are connected by a rope that hangs over a pulley as shown below. the pulley is a uniform cylinder of radius 푅=0.381meters and mass 푀=3.1푘푔. initially 푚"is on the ground and 푚#rests 2.5 meters above the ground. if the system is released, use conservation of energy to determine the speed of 푚#just before it strikes the ground. assume the pulley bearing is frictionless.

Abeam of light shining from water to air strikes the surface at an angle greater than 48 degrees and produces total internal reflection. if the incident beam is at a 50 degree angle what angle is the reflected beam 13 25 50 100