wiz-icon
MyQuestionIcon
MyQuestionIcon
1
You visited us 1 times! Enjoying our articles? Unlock Full Access!
Question

After the external resistance of a circuit has been increased 5 times, the voltage across the battery terminals increases from 10V to 30V. The emf of the battery is

A
60V
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
B
30V
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
40V
No worries! We‘ve got your back. Try BYJU‘S free classes today!
D
50V
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

The correct option is A 60V
Case 1
I=ER+r
P.D across battery =IR
=ERR+r=10 ........(1)
Case 2
I=E5R+r
P.D across battery =I(5R)
=5ER5R+r=30 .......(2)
Dividing (1) by (2)
5R+r5(R+r)=1315R+3r=5R+5r
2r=10R
r=5R
ERR+5R=10ER6R=10E=60V

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Electric Potential and Potential Difference
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon