The correct answer is:
<span>The rate at which a waves energy flows through a given unit of area
In fact, light intensity is defined as the light power per unit of area:
</span>
<span>but the power is the energy carried by the light per unit of time:
</span>
<span>this means that the intensity can be rewritten as
</span>
<span>
So, it's basically the rate of energy (per unit of time) through a given surface.</span>
Greetings
and james west is ALIVE
If the atom is neutral, it has the same number of protons as electrons. If there are 5 electrons, there are also 5 protons.
Answer:
The observer sees the space-probe 9.055m long.
Explanation:
Let be the length of the space-probe when measured at rest, and be its length as observed by an observer moving at velocity , then
Now, we know that and , and putting these into we get:
Thus, an observer moving at 0.95c observes the space-probe to be 9.055m long.
Kinetic energy = (1/2) (mass) (speed)²
The rock's kinetic energy is not
(1/2) (4 kg) (10 m/s)²
= (1/2) (4 kg) (100 m²/s²)
= 200 Joules .
It may be more, or it may be less. The only thing
we can be sure of is that it is not 200 Joules.