A football is thrown vertically upwards and reaches its maximum height after 4.50 seconds. a. What is the acceleration of the football at its maximum height? [1]
b. What is the initial velocity of the football? [2]

c. What is the maximum height reached by the football? [2]

d. Use the graph paper at right to sketch a qualitative velocity-time
graph for the motion of the ball as it comes up AND back down.
You do not need to fill in numbers, but you may if it helps. [1]

newton's first law of motion

the answer is a 3.8cm

explanation:

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.