3. In 1990, Gary Stewart of California made 177 737 jumps on a pogo Stick. Suppose that the pogo stick reaches a height of 12.0 cm with each
jump and that the average net force acting on the pogo stick during the
contact with the ground is 330 N upward. What is the time of contact
with the ground between the jumps? Assume the total mass of Stewart
and the pogo stick is 65 kg. (Hint: The difference between the initial
and final velocities is one of direction rather than magnitude.)

the results is a decrease in air temperature with an increase of altitude.

explanation:

the duration of a photographic flash is related to an rc time constant, which is 0.100 μs for a certain camera.

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.

im srry but ur wrong the answer is d a smooth rock, some red dirt, and an empty bird's nest.