Current Electricity and Electrical InstrumentHard
Question
In the circuit shown in figure, A is a sliding contact which can move over a smooth rod PQ. Resistance per unit length of the rod PQ is 1 ohm/m. Initially slider is just left to the point P and circuit is in the steady state. At t = 0 slider starts moving with constant velocity v = 5 m/s towards right. Current in the circuit at t = 2 sec is :-
Options
A.1 amp
B.less than 0.5 amp
C.more than 1 amp
D.in between 0.5 to 1.0 amp
Solution
30 - L 
= i (20 + 5t)
∵
= - ve
⇒ 30 - L
> 30
⇒ at t = 2sec ; i > 1 amp
= i (20 + 5t) ∵
= - ve⇒ 30 - L
> 30 ⇒ at t = 2sec ; i > 1 amp
Create a free account to view solution
View Solution FreeTopic: Current Electricity and Electrical Instrument·Practice all Current Electricity and Electrical Instrument questions
More Current Electricity and Electrical Instrument Questions
Current sensitivity of a moving coil galvanometer is 5 div/mA and its voltage sensitivity (angular deflection per unit v...A cell of emf ε and internal resistance r drives a current i through an external resistance R....The efficiency of a cell when connected to a resistance R is 60%. What will be its efficiency if the external resistance...A 5V battery with internal resistance 2Ω and a 2V battery with internal resistance 1Ω are connected to a 10	...For the two cells having same EMF E and internal resistance $r$, the current passing through the external resistor $6\Om...