Answer A is incorrect
A crest is just one point. It is not the distance between 2 crests.
B is incorrect
A trough is just 1 point. It is not the distance between 2 troughs.
C is incorrect.
the amplitude measures the height of a crest from the middle of the wave to the crest (or trough).
D is the correct answer. That is the distance between 2 crests or 2 troughs
It is eight times more than the star A.
<h3>What is luminosity and on which it depends?</h3>
The luminosity of an object is a measure of its intrinsic brightness and is defined as the amount of energy the object emits in a fixed time.
luminousity depends upon the two factors are:
1) The star's actual brightness
Some stars are naturally more luminous than others ,so the brightness level from one star to next star is significantly different.
2) The star distance from us
The more distance of an object the dimmer it appears.
Energy emitted = sAT⁴
where s is stefan constant
A is surface area and T is temperature .
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<span>Examples of outside forces acting on a car is gravity, wind, and other cars. Cars do not slide down hills because their weight, combined with the friction of their tires against the road, hold them in place. </span>
Newton´s thrid law of motion states that:
Every action has an equal and opposite reaction.
c. equal, opposite.
Explanation:
Hydraulic systems use the pump to push hydraulic fluid through the system to create fluid power. The fluid passes through the valves and flows to the cylinder where the hydraulic energy converts back into mechanical energy. The valves help to direct the flow of the liquid and relieve pressure when needed