The electrons in an atom exist in various energy levels. When an electron moves from a lower energy level to a higher energy level, energy is absorbed by the atom. When an electron moves from a higher to a lower energy level, energy is released (often as light).
The following equations show how kinetic energy (KE), potential energy (PE), and total mechanical energy (ME) are solved.
KE = 0.5mv²
PE = mgh
ME = PE + KE
where m is mass, v is speed/velocity, g is gravitational constant, and h is height.
Substituting for number 1,
KE = 0.5(2000 kg)(30 m/s)² 900,000 J
PE = (2000 kg)(9.8 m/s²)(0 m) = 0
ME = 900,000 J
I believe you will be able to answer the rest of the items following the same principles as presented above.
Answer:
Is a version of the law of conservation of energy
It’s hypothesis because it’s not backed up but it’s evidence for it to be true
A child swings her 40 cm (0.4 meter) long, straight arm around her shoulder joint at a 13 rad/s angular velocity. So, her hand is moving at 5.2 m/s every second.
<h3>What does angular velocity mean?</h3>
angular velocity is the speed where an object rotates or revolves around an axis or alters the angle between two bodies. The angle between a line solely on a single body and a line on the other in the illustration serves as a representation of this displacement.
<h3>In what way does angular velocity rise?</h3>
The angular velocity increases with increasing rotational angle over a certain period of time. Degrees per second (o/s), radians per second (rad/s), or revolutions per minute (rpm), if appropriate, are the units for angular velocity. An element of a vector is angular velocity.
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