Answer:
the action of measuring something.
Measurement is a comparison of an unknown quantity with a known fixed quantity of the same kind. The value obtained on measuring a quantity is called its magnitude. Magnitude of a quantity is expressed as numbers in its units.
Answer:
The height reached is 20m, The time taken to reach 20m is 2 seconds
Explanation:
Observing the equations of motion we can see that the following equation will be most helpful for this question.

We are given initial velocity, u
We know that the stone will stop at its maximum height, so final velocity, v
Acceleration, a
And we are looking for the displacement (height reached), s
Substitute the values we are given into the equation

Rearrange for s



s = -20 (The negative is just showing direction, it can be ignored for now)
The height reached is 20m
Use a different equation to find the time taken

Substitute in the values we have

Rearrange for t



t = 2s
The time taken to reach 20m is 2 seconds
Answer:
Option (b) is correct.
Explanation:
Elastic collision is defined as a collision where the kinetic energy of the system remains same. Both linear momentum and kinetic energy are conserved in case of an elastic collision.
Inelastic collision is defined as a collision where kinetic energy of the system is not conserved whereas the linear momentum is conserved. This loss of kinetic energy may due to the conversion to thermal energy or sound energy or may be due to the deformation of the materials colliding with each other.
As given in the problem, before the collision, total momentum of the system is
and the kinetic energy is
. After the collision, the total momentum of the system is
, but the kinetic energy is reduced to
. So some amount of kinetic energy is lost during the collision.
Therefor the situation describes an inelastic collision (and it could NOT be elastic).
Answer:
When you have to do an English-Metric (SI) length conversion, and you already know the English units of length (miles, yards, feet, inches, etc.), all you need to remember is one simple relationship, and you can readily convert any length in the SI system, to the equivalent length in the other.
1 foot (ft) = 0.3048 meters (m)
BIn this case you need your answer in inches. You (hopefully) know there are 12 inches in a foot, so you just do the following:
1 inch (in) = 1/12 ft = 0.3048/12 m = 0.0254 m
<span>An atom’s emission of light with a specific amount of energy confirms that </span><span>electrons emit and absorb energy based on their position around the nucleus.
The light emitted from an electron is a result of the electron's quantum jumps/leaps ( atomic electron transitions ) to and from different energy levels.</span>