Answer:
2450 J
Explanation:
Given that,
A 50Kg girl jumps off a 5-meter-high diving board.
We need to find the kinetic energy of the girl before she hits the water. At this point the kinetic energy becomes equal to the potential energy such that,
So, her kinetic energy right before she hits the water is equal to 2450 J.
For the same wave, the product product of
(wavelength) times (frequency)
is always the same number. (It happens to be the speed of the wave.)
So if one of them changes, the other one has to change in the opposite
direction, in order to keep their product constant.
For electromagnetic waves, higher frequency means higher energy.
I'm not sure about mechanical waves just now.
Answer:
A.−2.1 × 10^10 N
Explanation:
Using the formula;
E = k Q1Q2/d²
Where;
E is the electrical force
k is the constant
Q1, Q2 are the two charges and
d is the distance between the two charges
Therefore;
E = (9 x 10^9) × (0.0042) × (-0.0050) / (0.0030)²
= -2.1 x 10^10 N
Therefore; electrical force acting between the two charges is -2.1 x 10^10 N.
