A stone is projected vertically upwards with a velocity of 12ms'. Calculate or find: a) How long it took the stone to reach its maximum height.

b) Maximum height reached by the stone.

The acceleration of the stone will be -9.8 m/s^2, because of the acceleration of earth's gravity, the initial velocity will be 12 m/s, and the final velocity will be 0 m/s. Therefore, we can solve using a kinematic equation to solve the problems:

a)

Final Velocity = Initial Velocity + Acceleration * Time

0 = 12 + -9.8*t

-12 = -9.8*t

t = 12/9.8 ≈ 1.224

Therefore, the time is equal to 12/9.8 ≈ 1.2245 seconds.

b)

Displacement = (Initial Velocity + Final Velocity)/2 * Time

d = (12+0)/2*1.2245

d = 6*1.2245

d = 7.347

Therefore, the maximum height is approximately equal to 7.347 meters.

The refractive index is used to measure how much light bends as it goes from one medium to another the refractive index of air =1 as light doesn’t bend in it

When looking into a glass of water with a straw the straw may appear bent or morphed as the water has a different refractive index to air (and the light is passing from air to glass of water)