Answer: Option (b) is the correct answer.
Explanation:
It is known that when a ray of light tends to travel from a denser to rarer medium then there occurs total internal reflection.
For a denser medium the refractive index is greater than that of a rarer medium. This means that for the given situation refractive index of medium 
is greater than medium 
.
this also means that incident angle must be greater than the critical angle of the medium.
Thus, we can conclude that the statement > must be true for total internal reflection to occur.
Answer:
When the object in creases or decreases in temperature.
Explanation:
Heat flow moves energy from a higher temperature to a lower temperature. The bigger the difference in temperature between two objects, the faster heat flows between them. When temperatures are the same there is no change in energy due to heat flow. Radiation and Conduction are the two methods of heat transfer..
Answer:
300 J
Explanation:
Work = (Force)*(distance) = 600 N ∗ 0.5 m = 300 J
Answer:
<h2>9.8 m/s²</h2>
Explanation:
<h2>Since the ball rises for 2.5 s, the time to fall is 2.5 s. The acceleration is 9.8 m/s2 everywhere, even when the velocity is zero at the top of the path. Although the velocity is zero at the top, it is changing at the rate of 9.8 m/s² downward.</h2>
So you subtract the numbers that are on the same axis. So if your gravitational force is 10 and your normal force is 5 you do 5-10 to get -5 since gravity acts downward
