A natural force of attraction exerted by the earth upon objects, that pulls objects towards earth's center is called<u> </u><u>G</u><u>ravitational</u><u> </u><u>force</u><u> </u><u>.</u>
Answer: False
Explanation:
Relative to the concept of radiations, a black body is an object capable of absorbing any form of electromagnetic radiation irrespective of its frequency or angle of incidence when incident on such object.
However, the same cannot be said about real bodies as real bodies are those which reflect all rays incident on them completely and uniformly in all directions.
One very important characteristic of black bodies is that they are ideal emmiters.
The concept of emmisivity is brought about by the existence of real bodies .
This is due to the fact that they are only able to emit radiation at a fraction of the black body energy levels.
Please note that by convention, the emmisivity of a real body is always less thaan 1.
As such they are not able to emit as much radiation as a black body at the same temperature.
Is the physical property of matter that causes it to experience a force when placed in an electromagnetic field. Two types of electric charges are positive and negative.
.Explanation:
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Answer:
Potential Energy = 294J, Kinetic Engergy = 48.02J
Explanation:
We have these formulas:
Potential Energy = mass * gravitational force * height (m) = 1 * 9.8 * 30 = 294(J)
Kinetic Energy = 1/2 * mass * velocity^2 = 1/2 * 1 * 9.8^2 = 48.02 (J)
As the rock falling at an acceleration of 9.8m/s^2 which means for each second, the rock increases 9.8m/s. I think we are missing time to find the instantaneous velocity, the formula is (initial displacement - final displacement)/ (initial time - final time) which will directly give the final answer for you.
