Answer:
The speed is the same as long as the reflection is regular.
Explanation:
This is because in regular reflection, the angle of incidence is equal to the angle of reflection in accordance with the second law of reflection.
Since speed of light depends on the angle of the light ray it makes with the reflecting surface, the speed is the same
The answer is B. Sunlight (white light) refracts when it passes through droplets of water in the atmosphere
C
Terminal velocity is the maximum velocity attainable by an object as it falls through a fluid (air is the most common example). It occurs when the sum of the drag force (Fd) and the buoyancy is equal to the downward force of gravity (FG) acting on the object.(Wikipedia)
Solution: C. Pangea
The hypothesis of Continental drift suggests that in past, there was only one landmass on the Earth -Pangaea which drifted apart due to movement of plate tectonics causing earthquake. This hypothesis is supported by many evidences which includes presence of similar fossils on different landmasses, common land features such as widespread presence of glacial sediments etc.
Answer:
A.) 4.81 seconds
B.) 44.6 m/s
Explanation:
He begins his dive by jumping up with a velocity of 5 (m/s).
Let us first calculate the maximum height reached by using third equation of motion
V^2 = U^2 - 2gH
At maximum height, V = 0
0 = 5^5 - 2 × 9.8H
19.6H = 25
H = 25 /19.6
H = 1.28 m
The time taken for the diver to reach the water from the maximum height can be calculated by using second equation of motion.
Where height h = 1.28 + 100 = 101.28 m
h = Ut + 1/2gt^2
As the diver drop from maximum height, U = 0
101.28 = 1/2 × 9.8 × t^2
4.9t^2 = 101.28
t^2 = 101.28/4.9
t^2 = 20.669
t = sqrt ( 20.669)
t = 4.55s
As the diver jumped up, the time taken to reach the maximum height will be
Time = 1.28 / 5 = 0.256
The time taken for him to hit the water below will be 0.256 + 4.55 = 4.81 seconds
B.) Velocity right before he hits the water will be
V^2 = U^2 + 2gH
But U = 0
V^2 = 2 × 9.8 × 101.28
V^2 = 1985.09
V = 44.6 m/s
