To solve this problem, we use the formula:
I100 / I1 = [P / 4π(100m)^2] / [P / 4π(1m)^2]
I100 / I1 = 1 / 100^2
I100 / I1 = 10^-4
Therefore the change in intensity from 1m to 100m in decibels is:
B100 – B1 = 10 log(10^-4) dB = -40 dB
So the intensity at 100m is calculated as:
B100 = B1 – 40 dB = 140 dB – 40 dB = 100 dB
Answer:
100 dB
Answer:
a. reflection of all the light at a surface.
Explanation:
When light rays passing from the denser medium to the rarer medium and the angle of incidence is greater than the critical angle, the refraction of light does not take place and the incident ray is totally reflected back into the denser medium. This phenomenon is called total internal reflection.
There are two conditions that need to be fulfilled in order for the total internal reflection to take place:
1. The ray of light should be incident from denser to rarer medium.
2. The angle of incidence should be greater than the critical angle.
Therefore, the correct option will be:
<u>a. reflection of all the light at a surface.</u>
Answer:
True
Explanation:
Most vehicle's cooling system contain a coolant that flows through certain passages in the engine, as the coolant moves through those passages it absorb heat from moving engine parts and the explosion of gasoline in the cylinders. the coolant is then stored back in a radiator which is responsible for transferring the heat from the coolant to the environment(air).
