A toy balloon is inflated with helium at a constant pressure that is 4.3x10ºPa. in excess of atmospheric pressure. If the balloon
inflates from a volume of 1.8x10-4m3 to 9.5x10-4m
3
how much
work is done by the balloon on the surrounding air?

Aheavy piece of hanging sculpture is suspended by a90-cm-long, 5.0 g steel wire. when the wind blows hard, the wire hums at its fundamental frequency of 80hz. what is the mass of the sculpture?

Two cannon balls weighing 18 kg and 24 kg are chained together and fired horizontally with a velocity of 165 m/s from the top of a 21-m wall. the chain breaks during the flight of the cannonballs and the 18-kg cannonball strikes the ground at t = 1.5 s, at a distance of 240 m from the foot of the wall, and 7 m to the right of the line of fire. determine the position of the other cannonball at that instant. neglect the resistance of the air.

Identify the type of heat transfer occurring when chocolate melts in your hand