Two lab carts are on a frictionless track, attached by a spring. The carts are pushed together by a student in a Physics lab, compressing the spring fully. The student lets go of the carts and they move in opposite directions as the spring extends. Which of the following statements describes what happens to the car/spring system after the cars are released?
A. The kinetic energy remains constant.
B. The kinetic energy increases.
C. The momentum remains constant.
D. The momentum increases.

Heena wants to measure the volume of a ball that is 24 cm across. how should she set up her equation?

During physical science, ms. greene challenged her students to produce an energy transformation. james and jill wrapped a 4-inch nail with a coil of fifty turns of wire. they connected one end of the coil to one terminal of a knife switch. they connected the other terminal of the knife switch to the battery. finally, they connected the end of the coil to the other terminal of the battery. james held the tip of a 1-inch nail near the flat end of the 4-inch nail. jill closed the knife switch quickly and then opened it. the 1-inch nail was pulled toward the 4-inch nail. what is the best explanation of why the nail moved? a) electrical energy was converted to mechanical energy in the 1-inch nail. b) the 4-inch nail became an electromagnet and the magnetic force attracted the 1-inch nail. c) the electric current in the 4-inch nail was converted to mechanical energy in the 1-inch nail. d) the 4-inch nail had a positive charge and the 1-inch nail had a negative charge. opposites attracted.

Aforce of 9.00 newtons acts at an angle of 19.0 to the horizontal. what is its component in the horizontal direction?