1) B. Energy is the ability to do work
2) C. Energy is conserved, it just goes from one form to another.
3) Work = Force x displacement
= 300 x 100 = 30,000 Joules
4) leaning a brick because no displacement is taking place.
5) They change the amount/strength or direction of the force needed.
6) Less force is needed and applied over a longer distance.
7) Heat is the flow of thermal energy from one object to another.
The distance between two basket ball sized aluminium balls is 9714 m.
Explanation:
Coulomb's law, or Coulomb's inverse-square law, is an experimental law of physics that quantifies the amount of force between two stationary, electrically charged particles. The electric force between charged bodies at rest is conventionally called electrostatic force or Coulomb force .
Coulomb's law formula => F = (k * Qb1 * Qb2)/r²
Given data :-
charge on ball 1 Qb1 = 6C
charge on ball 2 Qb2 = 14C
Force exerted F = 8000 N
k = 8.988 x 10^9 Nm²C−²(coulomb's constant).
substituting given values in the coulomb's formula
8000 = (( 8.988 x 10^9)*6*14)/r²
shifting r and 8000 to other sides
r² = (756 * 10^9)/8000
r = 9714 m.
Therefore the distance between two balls is r = 9714 m.
Answer
Given,
refractive index of film, n = 1.6
refractive index of air, n' = 1
angle of incidence, i = 35°
angle of refraction, r = ?
Using Snell's law
n' sin i = n sin r
1 x sin 35° = 1.6 x sin r
r = 21°
Angle of refraction is equal to 21°.
Now,
distance at which refractive angle comes out
d = 2.5 mm
α be the angle with horizontal surface and incident ray.
α = 90°-21° = 69°
t be the thickness of the film.
So,


t = 2.26 mm
Hence, the thickness of the film is equal to 2.26 mm.