4. A 2000 kg SUV traveling at 7 m/s south runs into the rear end of an 800 kg compact car sitting at a stop light in an elastic collision. If the compact car is
going forward at 7 m/s right after the collision, how fast is the SUV traveling?
5. Beaker and Honeydew are driving bumper cars. They spot each other across the
rink and head straight for each other at full speed. Honeydew and his car (130 kg
I
total) head east at 3.5 m/s while Beaker and his car (110 kg total) head west at
3.0 m/s. They have an elastic collision when they meet and Honeydew (and car)
bounces backwards at 2.4 m/s. What is Beaker's speed after the collision?

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.

Atwo-stage air compressor operates at steady state, compression 10m^3/min of air from 100 kpa and 300k to 1200 kpa. an intercooler between the two stages cools the air to 300k at a constant pressure of 350 kpa. the compression processes are isentropic. a) calculate the power required to run the compressor, in kw b) compare the result to the power required for isentropic compression from the same inlet state to the same final pressure.

Abar magnet cut in half will form a total ofpoles. a)fourb)eightc)two