A 4.28 m deep well acts as a closed pipe. When wind blows
across the top, what is the
fundamental frequency it creates?
(Speed of sound = 343 m/s)
(Unit = Hz)

Ahot-air balloonist, rising vertically with a constant speed of 5.00 m/s releases a sandbag at the instant the balloon is 40.0 m above the ground. after it is released, the sandbag encounters no appreciable air drag. compute the velocity of the sandbag at 0.250 s after its release.

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

Select all the correct answers. which three statements about electromagnetic radiation are true?