BITSAT2014PhysicsCurrent ElectricityActual
For the circuit (figure), the current is to be measured. The ammeter shown is a galvanometer with a resistance R _ G =60.00 converted to an ammeter by a shunt resistance r _ s =0.02 . The value of the current is
Options
- A0.79 ~A
- B0.29 ~A
- C0.99 ~A
- D0.8 ~A
Correct answer
C. 0.99 ~A
Step-by-step solution
R _ G =60.00 , shunt resistance, r _ s =0.02 Total resistance in the circuit is R _ G +3=63 Hence, I =3 / 63=0.048 ~A Resistance of the galvanometer converted to an ammeter is, R _ G r _ s R _ G + r _ s = 60 0.02 (60+0.02) =0.02 Total resistance in the circuit =0.02+3 =3.02 Hence, I =3 / 3.02=0.99 ~A