Circuits 1

What is the equivalent of 1 electron in coulombs?

1 electron = 1.602 × 10^-19 C

What is the equivalent of 1 C in statC?

1 C = 3 × 10^9 statC

What is the other term for statC?

esu

It is the energy supplied per charged particles

Electromotive Force

It is any directional movement of charged particles.

Electric Current

What is the formula of current?

I = Q / t

It is the property of material to oppose or limit current

Resistance

Resistance of material is affected by the following?

• type of material / resistivity

• length

• area

Rank the common materials from least resistivty to most

1. Silver

2. Copper

3. Gold

What is the formula for resistance?

What is the formula for resistivity?

What is the formula for conductance?

1 mil is equal to?

10^-3 inches

What is the formula for area of circular mil?

In PTC, if temperature increases, resistance […]

increases

In NTC, if temperature increases, resistance […]

decreases

What materials have positive temperature coefficient?

Conductors

What materials have negative temperature coefficient?

Insulators and Semiconductors

What is the formula of resistance with temperature effect?

It is the rate, per unit time, at which electrical energy is transferred by an electric circuit.

Power

1 hp is equal to?

746 W

1 eV is equivalent to how many Joules?

1 eV = 1.6 × 10^-19 J

1 kWh is equal to how many Joules?

1 kWh = 3.6 × 10^6 J

What are advantages of carbon composition resistors?

• cheapest

• wide range

• non-reactive

What are advantages of wire-wound resistor?

• high wattage rating

• accuracte and stable resistance

What are advantages of film type resistors?

• wide range

• non reactive

• tighter tolerance

• less sensitive to temperature and aging

• generates low noise

What is a potentiometer?

• 3 terminals

• wide range but limited current handling capabilities

• used as voltage divider

What is rheostat?

• 2 terminals

• limited range but high current handling capabilities

• connected in series with load

Explain four band color coding

1st - 1st digit
2nd - 2nd digit
3rd - multiplier
4th - tolerance

Explain five band color coding

1st - 1st digit
2nd - 2nd digit
3rd - 3rd digit
4th - multiplier
5th - tolerance

Explain 3 digit code

First 2 digits indicate numerical value, last digit indicates multiplier

Explain 4 digit code

First 3 digits indicate numerical value, last digit indicates multiplier

In alphanumeric coding, what does the first letter indicates? Enumerate them

Multiplier

R = x1
K = x1000
M = x1000000

In alphanumeric coding, what does the second letter indicates? Enumerate them

Tolerance

F = 1%
G = 2%
J = 5%
K = 10%
M = 20%

Give applications of capacitors

• block DC, allow AC

• block low frequencies, pass higher frequencies

• smoothing ripple

What is the formula of capacitance with charge and voltage?

C = Q / V

What is reciprocal of capacitance and its unit?

Elastance (daraf)

What is unit of capacitance with permittivity, area, and distance?

What is the formula of energy stored with capacitance?

What is the formula of capacitor current?