3. Jacob throws a bouncy ball (0.75kg) at Caroline with a speed of 3.1m/s. Caroline throws her heavier bouncy ball (2.5kg) towards Jacob. The bouncy balls collide in the air and travel in opposite directions, each ball has a speed of
2.0m/s. What was the initial speed of Caroline's ball? [G][0][E][S][S]

Consider an ordinary, helium-filled party balloon with a volume of 2.2 ft3. the lifting force on the balloon due to the outside air is the net resultant of the pressure distribution exerted on the exterior surface of the balloon. using this fact, we can derive archimedes’ principle, namely that the upward force on the balloon is equal to the weight of the air displaced by the balloon. assuming that the balloon is at sea level, where the air density is 0.002377 slug/ft3, calculate the maximum weight that can be lifted by the balloon. note: the molecular weight of air is 28.8 and that of helium is 4.

What are similarities and differences between refraction, reflection, diffraction and absorption?

How would a small bar magnet be oriented when placed at position x?