An electric motor is used in the compressor of a refrigerator. the motor is responsible for circulate the coolant liquid through two sets of coils: the compressor and the evaporator. in this case, the motor is
a. using the magnetic field to cool the refrigerator.
b. converting mechanical energy into electrical energy.
c. using a magnetic field to create electrical energy.
d. converting electrical energy into mechanical energy.

Ablock of mass m = 2.5 kg is attached to a spring with spring constant k = 790 n/m. it is initially at rest on an inclined plane that is at an angle of 28 degrees with respect to the horizontal, and the coefficient of kinetic friction between the block and the plane is k = 0.14. in the initial position, where the spring is compressed by a distance of a = 0.18 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. 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.

World class speed skaters can skate a 3,000-m course in about 4 minutes.what is their average speed for this course? a. 12.5 m/sb. 1.33 m/sc. 1.25 m/sd. 13.3 m/s

Matter is needed to transfer thermal energy bya. conductionb. convectionc. radiation d. both a & b.