Answer:
The velocity of the ball before it hits the ground is 381.2 m/s
Explanation:
Given;
time taken to reach the ground, t = 38.9 s
The height of fall is given by;
h = ¹/₂gt²
h = ¹/₂(9.8)(38.9)²
h = 7414.73 m
The velocity of the ball before it hits the ground is given as;
v² = u² + 2gh
where;
u is the initial velocity of the on the root = 0
v is the final velocity of the ball before it hits the ground
v² = 2gh
v = √2gh
v = √(2 x 9.8 x 7414.73 )
v = 381.2 m/s
Therefore, the velocity of the ball before it hits the ground is 381.2 m/s
Answer:
n1 sin θ1 = n2 sin θ2 Snell's Law (θ1 is the angle of incidence)
sin θ2 = n1 / n2 * sin θ1
sin θ2 = 2.4 / 1.33 * sin θ1
sin θ2 = 1.80 * .407 = .734
θ2 = 47.2 deg
Answer:

Explanation:
If we assume that the Earth is a spherical conductor, according to Gauss's Law, the electric field is given by:

Here k is the Coulomb constant, the excess charge on the Earth's surface and r its radius. Solving for q:

The process of refraction of light occurs when light rays bends when travelling between media of different densities.
What is refraction of light?
Refraction of light is the bending of light rays or the change in the direction of light rays as it travels between media of different densities.
Light waves travel faster in media of less density than media of more density.
The change in density of the media makes light waves to be bend towards or away from the normal.
For example, when light travels from less dense air to more dense water, the light rays are bent towards the normal. However, when light rays travel from water to air, the light rays are refracted away from the normal.
In conclusion, refraction of light waves occur when light crosses the boundary of media of different densities.
Learn more about refraction of light at: brainly.com/question/27932095
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