Answer:
Explanation:
Given that,
A lady falling has a final velocity of 4m/s
v = 4m/s
Mass of the lady is 60kg.
m = 60kg
Using conservation of energy, the potential energy of the body from the point where the lady is dropping is converted to the final kinetic energy of the lady.
Therefore,
P.E = K.E(final) = ½mv²
P.E = ½ × 60 × 4²
P.E = 480 J.
The average energy delivered to a surface is 7.5*10^6J.
To find the answer, we have to know about the poynting vector.
<h3>How to find the average energy delivered to a surface?</h3>
- Energy per time through a unit area perpendicular to the direction of propagation of EM wave is called poynting vector.
- We can write the expression of Poynting vector as,
where; E(avg) is the average energy of the EM wave, and c is the speed of light.
- We can rewrite the expression as per our defenition as,
- Thus, the value of average energy will be,
Thus, we can conclude that, the average energy delivered to a surface is 7.5*10^6J.
Learn more about the poynting vector here:
brainly.com/question/19530841
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Velocity = displacement/time
I hope i helped you <33