Answer:
1. Letter A indicates the crest.
2. Letter E indicates the wavelength.
3. Letter C indicates the trough.
Explanation:
1. Determination of the the crest.
A crest is simply defined as a point on a wave where the displacement is maximum (i.e highest).
Considering the diagram given above, the point where the displacement is maximum is A. Therefore, A is the crest of the wave.
2. Determination of the wavelength.
The wavelength of a wave is simply defined as the distance between two successive crest or trough.
Obeserving the diagram above, we can see that E gives the distance between two successive crest. Therefore, E is the wavelength of the wave.
3. Determination of the trough.
A trough is simply defined as a point on a wave where the displacement is minimum (i.e lowest). Thus we can say that the trough is the opposite of the crest.
Considering the diagram given above, the point where the displacement is minimum is C. Therefore, C is the trough of the wave.
Answer:
20 = 30 / t1
t1 = 3/2
40 = 30 / t2
t2 = 3/4
average speed = total distance / total time taken
= 30 + 30 / 3/2 + 3/4
= 60 /9/4
= 60 × 4/9
= 26.667
The Atlantic and Pacific<span> Canal </span>
The initial volume of the gas is
while its final volume is
so its variation of volume is
The pressure is constant, and it is
Therefore the work done by the gas is
where the negative sign means the work is done by the surrounding on the gas.
The heat energy given to the gas is
And the change in internal energy of the gas can be found by using the first law of thermodynamics:
where the positive sign means the internal energy of the gas has increased.