Definitions and Formulas for WA1

Question 1

Equation of State for an Ideal Gas

Answer 1

pV = nRT

Question 2

How many particles are there in one mole of any substance?

Answer 2

6.02 × 10²³

Question 3

Avagadro Number

Answer 3

6.02 × 10²³ mol⁻¹

Question 4

Basic Assumptions of the Kinetic Theory of Gases

Answer 4

1. A gas consists of large number of mo

Question 5

Mean square speed

Answer 5

pV = ⅓ Nm<c²>

Answer 6

½ m<c²> = ³⁄₂ kT

Question 7

Specific Heat Capacity

Answer 7

Specific heat capacity of a substance is defined as the amount of heat that must be supplied to it to cause a unit mass of the substance to undergo a unit rise in temperature without a change in state.

Question 8

Specific Latent Heat

Answer 8

Specific latent heat of a substance is defined as the amount of heat that must be supplied to it to cause a unit mass of the substance to undergo a change of state without a change in temperature.

Question 9

First Law of Thermodynamics

Answer 9

The first law of thermodynamics states that:
the increase in internal energy [ΔU] of a system is equal to the sum of the heat supplied to the system (Qₛ) and the work done on the system [Wₒₙ].

[ΔU = Qᵢₙ + Wₒₙ]

Question 10

Internal Energy of an Ideal Gas

Answer 10

U = ³⁄₂ nRT

Question 11

Electric Field Strength at a Point

Answer 11

Electric field strength at a point is defined as:
the electric force exerted per unit positive charge placed at that point.

Question 12

Coulomb’s Law (in Words)

Answer 12

Coulomb’s Law states that the magnitude of force between two point charges is directly proportional to the product of the magnitude of the two charges and inversely proportional to the square of their separation.

Question 13

Coulomb’s Law (Formula)

Answer 13

F = (1 / 4πε₀)(Q₁Q₂ / r²)
or
F = Q₁Q₂ / 4πε₀r²

Question 14

Electric Field Strength of a Point Charge (Formula)

Answer 14

E =  (1 / 4πε₀)(Q / r²)
or
E = Q / 4πε₀r²

Question 15

Electric Potential at a Point

Answer 15

Electric Potential at a Point is the work done per unit positive charge in bringing a small test charge from infinity to that point.

Question 16

Potential Gradient at a Point

Answer 16

Potential gradient at a point is the rate of change of potential with respect to distance.

[It is numerically equal to the field strength at the point and the field strength is in the direction of decreasing potential.]

Question 17

Electric Potential in the Field of a Point Charge

Answer 17

V =  (1 / 4πε₀)(Q / r)
or
V = Q / 4πε₀r

[V = Er]

Question 19

Magnetic Flux Density in a Long Straight Wire

Answer 19

B = μ₀𝐼 / 2πd

Question 20

Magnetic Flux Density in a Flat Circular Coil

Answer 20

B = μ₀N𝐼 / 2r

Question 21

Magnetic Flux Density in a Long Solenoid

Answer 21

B = μ₀n𝐼

Question 22

Fleming’s Left-Hand Rule (Formula)

Answer 22

F = B𝐼𝑙 sin θ
Related: F = BQv sin θ

Question 23

Magnetic Flux Density

Answer 23

Magnetic flux density of a field is defined as the magnetic force acting per unit current per unit length of a straight wire placed perpendicular to the magnetic field.

Question 24

Magnetic Flux (Definition)

Answer 24

Magnetic flux through a surface is defined as the product of the area and the component of the magnetic flux density perpendicular to that area.

Question 25

Magnetic Flux (Formula)

Answer 25

Φ = BA

Question 26

Magnetic Flux Linkage

Answer 26

Magnetic flux linkage through a coil is the product of the number of turns of the coil and the magnetic flux through each turn.

Question 27

Faraday’s Law of Electromagnetic Induction

Answer 27

Faraday’s law of electromagnetic induction states that the magnitude of induced e.m.f. is directly proportional to the rate of change of magnetic flux linkage. [E = −d(Nϕ) / dt]

Question 28

Lenz’s Law

Answer 28

Lenz’s law states that the direction of the induced e.m.f produced causes effect to oppose the change that produces it.