wiz-icon
MyQuestionIcon
MyQuestionIcon
2
You visited us 2 times! Enjoying our articles? Unlock Full Access!
Question

Two identical heater wires are first connected in series and then in parallel with a source of electricity. The ratio of heat produced in the two cases ?

A
2:1
No worries! Weā€˜ve got your back. Try BYJUā€˜S free classes today!
B
1:2
No worries! Weā€˜ve got your back. Try BYJUā€˜S free classes today!
C
4:1
No worries! Weā€˜ve got your back. Try BYJUā€˜S free classes today!
D
1:4
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
Open in App
Solution

The correct option is D 1:4
Answer is D.

The heat energy E = Pt = (VI)t = I2Rt(V=IR).
Since the wires are identical, their resistances are equal. Let their individual resistance be R.
In series, the equivalent resistance is R+R = 2R.
Therefore, E1 = I2(2R)t=2(I2Rt).
In parallel, the equivalent resistance = R22R.
Therefore, E2 = I2(R22R)t=I2Rt2.
E1/E2 = 1/4.
Hence, the ratio is 1:4.

flag
Suggest Corrections
thumbs-up
0
Join BYJU'S Learning Program
similar_icon
Related Videos
thumbnail
lock
Heating Effect of Electric Current
PHYSICS
Watch in App
Join BYJU'S Learning Program
CrossIcon