Explanation:
(a)
Critical angle is the angle at the angle of refraction is 90°. After the critical angle, no refraction takes place.
Using Snell's law as:
Where,
is the angle of incidence
is the angle of refraction = 90°
is the refractive index of the refraction medium
is the refractive index of the incidence medium
Thus,
The formula for the calculation of critical angle is:
Where,
is the critical angle
(b)
No it cannot occur. It only occur when the light ray bends away from the normal which means that when it travels from denser to rarer medium.
Answer:
ΔF=125.22 %
Explanation:
We know that drag force on the car given as

=Drag coefficient
A=Projected area
v=Velocity
ρ=Density
All other quantity are constant so we can say that drag force and velocity can be given as

Now by putting the values



Percentage Change in the drag force



ΔF=125.22 %
Therefore force will increase by 125.22 %.
The candle is giving off light
Chemical energy from the candle is converted to thermal energy
Answer:
Hope the above picture might help you :)
Answer:
Explanation:
Acceleration is the change in velocity with respect to time.
Acceleration = change in velocity/Time
Acceleration = final velocity - initial velocity/Time
Given initial velocity = 10m/s
Final velocity = 20m/s
Time taken = 4s
Acceleration = 20-10/4
Acceleration = 10/4
Acceleration =2.5m/s²
For the second part of the question:
Given parameters
initial velocity = 15m/s
acceleration = -3m/s²
time = 4seconds
a = v-u/t
-3 = v-15/4
cross multiply
-12 = v-15
add 15 from both sides
-12+15 = v-15+15
3 = v
<em>Hence the final velocity of the car is 3m/s</em>