Answer:
Correct sentence: gravitational potential energy of the mass on the hook.
Explanation:
The mechanical energy of a body or a physical system is the sum of its kinetic energy and potential energy. It is a scalar magnitude related to the movement of bodies and to forces of mechanical origin, such as gravitational force and elastic force, whose main exponent is Hooke's Law. Both are conservative forces. The mechanical energy associated with the movement of a body is kinetic energy, which depends on its mass and speed. On the other hand, the mechanical energy of potential origin or potential energy, has its origin in the conservative forces, comes from the work done by them and depends on their mass and position. The principle of conservation of energy relates both energies and expresses that the sum of both energies, the potential energy and the kinetic energy of a body or a physical system, remains constant. This sum is known as the mechanical energy of the body or physical system.
Therefore, the kinetic energy of the block comes from the transformation in this of the gravitational potential energy of the suspended mass as it loses height with respect to the earth, keeping the mechanical energy of the system constant.
For electrical devices . . .
Power dissipated = (voltage) x (current) =
(12 V) x (3.0 A) = 36 watts .
1 watt means 1 joule per second
(36 joule/sec) x (60 sec/min) x (10 min) = 21,600 joules
Vi = 2m/s
a= 4.5 m/s
d= 340 m
vf= ?
use this equation ... vf^2=vi<span>^2+2ad
you should get vf = 55.3
hope this helps </span>
Answer:
the source of sound moves towards an observe
Explanation:
The Doppler effect is related to waves such as sound or light. the effect causes an increase or decrease in the frequency of sound light or other waves when the souces either move towards or away from the observer. For example the siren of the train to a person on the platform, the redshift seen by astronomers.
Therefore, The Doppler shift can be observed when the source of sound moves towards an observer From a place closer to the observer than the last wave's crest, each consecutive wave crest is sent. Each wave therefore, takes a little less time than the preceding wave to reach the observer.