Ask a Doubt
Request a call back

Join NOW to get access to exclusive study material for best results

CBSE Class 12-science Answered

A battery of emf 2.5 V and internal resistance r is connected in series with a resistor of 45 ohm through an ammeter of resistance of 1 ohm. The ammeter reads current of 50 mA. Draw the circuit diagram and calculate the value of r.
Asked by Topperlearning User | 04 Jun, 2014, 01:23: PM
answered-by-expert Expert Answer
The total resistance of the circuit = 45 + 1 + r = (46 + r) ohm
Current = 50 x 10 -3 A
Emf = 2.5V
 Resistance = emf/current
(46 + r) ohm = 2.5 V/ 50 x 10 -3 A = 50 ohm
r= (50-46)ohm= 4 ohm.

Answered by | 04 Jun, 2014, 03:23: PM

Concept Videos

Multiple Choice Questions Practice Test
Answered Unanswered My Questions My Answers
CBSE 12-science - Physics
Req
question image
Asked by guptakartikgupta2 | 16 Jul, 2022, 05:23: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
in Current electricity, in section batteries and EMF, we studied that,in a battery a internal mechanism exerts forces on the charges of battery... sir can you please explain, how this force drives the charge in a battery and why these forces drive charges in that manner? please explain sir..
Asked by yashrajgharte24.12dgatl | 18 Aug, 2021, 09:29: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
What is potential gradient along the wire Reading of voltmeter  
question image
Asked by diyasinha1701 | 31 Jul, 2021, 09:58: AM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
pls solve
question image
Asked by sulaikhasulu393 | 29 Apr, 2020, 05:17: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
A battery of end E and internal resistance r is used in a circuit with a variable external resistance R. Find the value of R for which the power consumed in R is maximum.
Asked by prakriti12oct | 28 Jul, 2019, 11:07: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
By using the graph of terminal potential difference with external resistance how can we find internal resistance
Asked by rejimoljohn123 | 01 Jan, 2019, 09:08: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
A 9 V battery is connected in series with a resistor .The terminal voltage is found to be 8 V. Current through the circuit is measured as 5 A. What is the internal resistance of the battery?
Asked by ayushmittal2424 | 09 Dec, 2018, 09:45: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
Establish the expression for current flowing through an external resistance R connected to a cell of e.m.f. E and internal resistance r.
Asked by sd2021667 | 02 Dec, 2018, 09:09: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
Draw a circuit diagram for the comparying of emf of two primary cell using a potentiometer
Asked by rohitbansal39295 | 15 Nov, 2018, 09:00: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
CBSE 12-science - Physics
two cells of voltage 10 v and 2 v and internal resistances of 10ohm and 5 ohm respectively, are connected in parallel with positive end of 10v battery connected to negative pole of 2v battery.find the effective voltage and effective internal resistance of the combination.
question image
Asked by my3shyll | 24 Sep, 2018, 07:33: PM
ANSWERED BY EXPERT ANSWERED BY EXPERT
My Class Videos Tests ₹ Plans Ask a Doubt
Get Latest Study Material for Academic year 24-25 Click here
×