In tennis, one of the primary ways to win a point is by making the ball bounce twice on your opponent's side of
the court. A tennis player hits a ball at a velocity of 50
m/s at a 0 degree angle from 1m high. When the ball
bounces it reflects its velocity angle perfectly and loses
30% of its speed.

How long does the other player have to return the ball
before the second bounce?

Specific heat refers to the amount of heat required to change 1 gram of a substance by degree(s) celsius

Select light for the type of wave, adjust the wavelength so that the light is red, and increase the amplitude of the light to the max. then, select the start button at the source location to begin producing the waves. light is a form of electromagnetic wave, containing oscillating electric and magnetic fields. the wave amplitude detector mentioned above shows how the electric field oscillates in time at the location of the probe. the amplitude of the wave at the location of the probe is equal to the maximum electric field measured. how does the amplitude of the wave depend on the distance from the source?

Is a volume of space that is empty of matter.