The critical angle is the angle of incidence which gives 90 degrees refraction of light. If the incident angle is less than the critical angle, the ray of light will penetrate the second medium and if the incident angle is more than the critical angle, the ray will not penetrate and total internal reflection will occur.
So, to decide whether the ray will penetrate or not, we need to calculate the critical angle and compare it with the incident angle.
critical angle is calculated using the following rule:
critical angle = arcsin (n2 / n1) where
n1 is that of the oil = 1.47
n2 is that of the water = 1.33
therefore,
critical angle = arcsin (1.33 / 1.47) = 64.79 degree
Since the incident angle is greater than the critical angle, therefore the ray will not penetrate and will undergo total internal reflection.
Answer:
6m
Explanation:
The initial potential energy of the block P.E =mgh
where mass m = 3kg
g= 9.81 m/s2
h = 2m
Hence P.E = 3*9.81*2 = 58.8 Joules
This energy converts to kinetic energy when the block is released from the top
K.E = 
Solving for v, we obtain 6.26 m/s
The acceleration of the block by Newton's second law of motion,
ma = (μk)*mg
where μk = 0.1
Hence, a = 0.1*9.81 = 0.98m/s/s
Applying Newton's second equation of motion to solve,

where u = 0 m/s (released from rest0
Hence, 
Solving for s,
s= 20m
Therefore, the distance after two complete cycles = 20 -2(7) = 6m
Answer:
Car first should be 30.13 m behind the second car.
Explanation:
Given that,
Constant speed = 108.5 Km/hr
Time = 1 sec
Let the distance covered by second car S and by first car S'
We need to calculate the distance covered by second car
Using equation of motion
.....(I)
The distance covered by first car to avoid collision

Put the value into the formula
...(II)
We need to calculate the distance covered by first car
Using equation (I) and (II)

Put the value into the formula


Hence, Car first should be 30.13 m behind the second car.
Hello There!
It is Spring potential energy. Also called Elastic potential energy.
Hope This Helps You!
Good Luck :)
- Hannah ❤
Energy is released to the environment.