-- Kinetic energy is the energy of mass in motion. The amount is determined by the mass of whatever is moving, and its speed.
-- Potential energy is the energy that's stored up in some form, not being used yet but ready to be used when you want it.
For example, one form of it is <u><em>chemical</em></u><em> </em>potential energy, like in a battery, or a match. You get the energy out of a battery when you connect it to a motor or a light. You get the energy out of as match when you make the tip hot and it flares up.
This question is asking about <u><em>gravitational</em></u> potential energy. An object has stored energy just by being up high, like a bowling ball on a shelf. You get the energy out of it just by dropping it ... possibly enough to crack the floor !
The amount of this kind of potential energy is determined by the mass of the object, and how high up it is.
-- Getting the answers from other people doesn't help you a bit, until you understand them and can answer the question on your own.
Answer:
15/f s
Explanation:
The refractive index n = 1.5 of the glass is n = λ₁/λ₂ where λ₁ = wavelength of monochromatic light in vacuum = L/10 and λ₂ = wavelength of monochromatic laser in glass.
So, λ₂ = λ₁/n.
We know the speed of light in glass, v = fλ₂ and λ₂ = v/f.
The light covers a distance d = L in time, t = d/v (since v = d/t)
So, the time it takes the pulse of light to travel from one end of the glass to the other is t = d/v = L/fλ₂ = L/fλ₁/n = nL/fλ₁ = nL/fL/10 = 10 × 1.5/f = 15/f s
So, the time it takes the pulse of light to travel from one end of the glass to the other is t = 15/f s
Answer: The correct answers are (A) and (C).
Explanation:
The expression from electrostatic force is as follows;
Here, F is the electrostatic force, k is constant, r is the distance between the charges and 
are the charges.
The electrostatic force follows inverse square law. It is inversely proportional to the square of the distance between the charges. It is directly proportional to the product of the charges.
Like charges repel each other. There is a force of electrostatic repulsion between the like charges. Unlike charges attract each other. There is a force of electrostatic attraction between unlike charges.
The charges are induced on the neutral object when it is placed nearby the charged object without actually touching it.
Therefore, the true statements from the given options are as follows;
Like charges repel.
Unlike charges attract.
Answer:
The photoelectric effect is a phenomenon in which the photoelectrons are emitted from the metal when an incident electromagnetic wave hits the metal. The incident light should have a threshold frequency to meet the work function of the metal
