The Celsius degree is the same size as the Kelvin.
The correct choice is 'C'.
I., II., and IV. are examples of acceleration. III. isn't.
Answer:
The initial velocity of the ball is <u>39.2 m/s in the upward direction.</u>
Explanation:
Given:
Upward direction is positive. So, downward direction is negative.
Tota time the ball remains in air (t) = 8.0 s
Net displacement of the ball (S) = Final position - Initial position = 0 m
Acceleration of the ball is due to gravity. So, 
(Acting down)
Now, let the initial velocity be 'u' m/s.
From Newton's equation of motion, we have:
Plug in the given values and solve for 'u'. This gives,
Therefore, the initial velocity of the ball is 39.2 m/s in the upward direction.
The right answer is b) copper
<h2><u>Question</u> :</h2>
When an athlete perspires after running
- Evaporation occurs and helps to cool the body.
- Convection cools the body.
- The body absorbs cold from the surrounding air.
- Heat is conducted away from the body.
<h2><u>Answer</u> :</h2>
When an athlete perspires after running evaporation occurs and helps to cool the body.
Correct option is A.
<h2><u>Explanation</u> :</h2>
When an athlete perspires after running then sweat evaporates and we know that evaporation causes cooling as evaporation requires heat energy. The required heat energy is taken away by the molecules of sweat when they convert from liquid into gas, and this causes cooling on the surface of body. That's why it helps to cool the body.
