Object a has mass m and is traveling forward with speed v. which set of changes to object a will not affect its momentum?
mass reduced to 0.5m, speed increased to 2v

mass reduced to 0.25m, speed increased to 1.25v

mass increased to 2m, speed increased to 2v

the direction of velocity reversed, speed kept at v

What is work? how much work is done to move an object 0 meters?

The law of reflection states that the angle of reflection is equal to the angle of

A47.2 g block of copper whose temperature is 480 k is placed in an insulating box with a 91.8 g block of lead whose temperature is 200 k. (a) what is the equilibrium temperature of the two-block system? (b) what is the change in the internal energy of the two-block system between the initial state and the equilibrium state? (c) what is the change in the entropy of the two-block system? the heat capacities of copper and lead are 386 j/kg·k and 128 j/kg·k, respectively.