## Electricity PYQs Solution PDF Download

## All Formulas of Electricity:

1) I = Q/t

2) Q = ne

3) V = W/Q

4) V = IR

5) R = Rho x L/A

6)Resistance in Series: Rs = R1 + R2 + R3

7)Resistance in Parallel: 1/Rp = 1/R1 + 1/R2 + 1/R3 (» Reciprocal of R1+R2+R3)

8)H = V × Q i) H = VIt ii) H = I²Rt iii) H = V²t/R

9) P = W/t i) P = VI ii) P = I²R iii) P = V²/R

10) E = P × t S.I.

**Units:**

Current ( I ) – Ampere

Charge ( Q ) – Coulomb

Time ( t ) – Second

Potential Difference or Voltage ( V ) – Volt

Resistance ( R ) – Ohm Ω

Resistivity ( Rho ) – Ohm meter

Power ( P ) – Watt

Heat = Energy = Work = Joule

**Measuring Devices:**

Ammeter / Milli Ammeter – for measuring current (always connected in series)

Galvanometer – for measuring small/sensitive currents (we can also get the direction of the current)

Voltmeter – for measuring volts (always connected in parallel)

Ohm Meter – Measures the resistivity

Least Count = First Value/No. Of Divisions

**Things to remember**:

electron charge = (1.6 x 10⁻¹⁹ C)

1kWh= 3.6 × 10⁶J

1Ampere = 1000mA

1 Kilowaat = 1000W

1 Horse Power = 746W