Physics Questions and Answers

Earthing of an electrical appliance meant the outer metallic case of appliance is connected with earth, wire which is welded to the end of a copper rod and it is burned in the ground. It save the appliance during short-circuiting by passing Excessive current to earth

P = 60w, V = 240v, R = ?

P = $\frac{V^2}{R}$

: 60 = $\frac{240^2}{R}$

→ R * 60 = 57,600

R = $\frac{57,600}{60}$

R = 960$\Omega$

Since the current flowing through a parallel resonance circuit is the product of voltage divided by impedance, at resonance the impedance, Z is at its maximum value.

 (Z=R )

Moderation is the process of the reduction of the initial high speed (high kinetic energy) of the free neutron.

Since energy is conserved, this reduction of the neutron speed takes place by transfer of energy to a material called a moderator.

There are several different types of moderating materials, and each have places where they are used more effectively.

Typically-used moderator materials include heavy water, light water, and graphite.

Given Data: L = 10, V = 50, F = 100, I = ?

Inductive Reactance [X$_L$] = 2$\pi$FL → 2 * 3.14 * 100 * 10

X$_L$ = 6,280

Current[I] = $\frac{V}{X_L}$ → $\frac{50}{6280}$

I = 0.0079 

≈ 0.008A