A physics professor demonstrates the Doppler effect by tying a 900 Hz sound generator to a 1.0- m -long rope and whirling it around her head in a horizontal circle at 100 rpm . 1. What is the difference between the highest frequency heard by a student in the classroom and the initial frequency of the sound generator?
2. What is the difference between the lowest frequency heard by a student in the classroom and the initial frequency of the sound generator?

A250-n box is at rest on a frictionless horizotal floor. then a person shoves the box with a non-zero force of magnitude p. which statement best describes the relationship betweeen p and the motion of the box after it was shoved? -the box will not move when p< 250n but otherwise will accelerate at a constant rate that is directly proportional to p - the box will begin moving at a speed that is directly proportional to p, then will gradually slow to a halt -the box will move with constant velocity at a speed that is directly proportional to p -box will accelerate across the floor at a constant rate that is directly proportional to p

Write down two additional questions about earth's magnetic field that will make your presentation more informative.

Which pair of quantities includes one quantity that increases as the other decreases during simple harmonic motion?