As a person pushes a box across a floor, the energy from the person's moving arm is transferred to the box, and the box
and floor become warm. during this process, energy is
save and exit

What is tan(61)? а. 1.80 b. 0.49 c. 0.61 d. 0.87

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 710 n/m. it is initially at rest on an inclined plane that is at an angle of θ = 23° with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is μk = 0.19. in the initial position, where the spring is compressed by a distance of d = 0.16 m, the mass is at its lowest position and the spring is compressed the maximum amount. take the initial gravitational energy of the block as zero. a) what is the block's initial mechanical energy? b) if the spring pushes the block up the incline, what distance, l, in meters will the block travel before coming to rest? the spring remains attached to both the block and the fixed wall throughout its motion.

If two parallel light rays hit a mirror, they will not be parallel to each other after they reflect.