Answer:

Explanation:
m = Mass of person = 70 kg
c = Specific heat of human body = 
= Change in temperature
Time taken is 1 hour
Heat is given by

The rise in temperature is 
Answer: C and D
Explanation: One of the first rule for total internal reflection to occur is that the ray must move from a dense to a less dense medium, hence refractive index of medium a must be greater than that of b.
When a ray moves from a dense to a less dense medium, the refracted ray moves away from the normal thus increasing the size of the angle of refraction (total internal refraction occurs when the angle of refraction is 90° and the angle of incidence at this point is known as the critical angle), hence the angle of incidence must be greater than the critical angle.
These points verifies option C and D
Answer: Angle 59 degree
Explanation: Given that the
n1 = 1.0
n2 = 1.5
Øi = 35 degree
From Snell law, which says that
n1/n2 = sinØ1/ sinØ2
Substitute all the parameters into the formula
1/1.5 = sin 35/sinØ2
Cross multiply
Sin Ø2 = 1.5 sin35
SinØ2 = 1.5 × 0.573 = 0.860
Ø2 = sin^-1(0.860)
Ø2 = 59.36 degree
Ø2 = 59 degree ( approximately)
It has angle 59 degree when passing from air to glass
Explanation:
We have,
Distance traveled in a circular track is 500 miles
The winning time was 3 hours and 13 minutes. It means time is 3.217 hours.
The driver's average speed is given by total distance divided by total time taken. Its formula can be written as :

At the end of the race, the driver reaches the point form where he has started. It means the displacement of the driver is equal to 0. Hence, driver's average velocity is equal to 0.
Answer:
D. Exothermic, because energy is being absorbed from the surroundings
Explanation:
This is true about the Exothemic reaction due to the fact that, the reaction occurs outside the body. During this reaction, the energy being absorbed <em>from the surrounding environment will hit the body surface thereby creating the coldness due to the heat given out from the body being minimal.</em>