Question

Previous year Jee mains question

chapter :- magnetic effect of current . ​

Answer 1

Answer:

answers is A 10³ is right answer I think so

Answer 2

option ( c) 9995Ω

Explanation:

Given :- Galvanometer has 150 equal divisions .

current sensitivity is 10 division per milliampere

and voltage sensitivity is 2 division per milliampere

Full scale deflection current = 150/10 mA = 15mA

Full scale deflection voltage = 150 /2 = 75mV

Galvanometer resistance, G = 75/15 = 3Ω

Required full scale deflection voltage v,

V = 1× 150 = 150V

Let resistance to be connected in series R .

• → V = Ig(R+G)

• → ∴ 150 = 15 × 10⁻³ (R + G)

• or, 10⁴ = R + 5

• Or, R = 1000 - 5 = 9995Ω

Resistance in ohms needed to connected in series with the coil will be 9995