Verified Solution • 2025–26 Session
moderate
QJEEM23Phfaba: JEE Main 2023 Physics - Class 12 JEEM23Phfaba Solution: A potential is applied across a uniform wire of resistance .…
A potential is applied across a uniform wire of resistance . The power dissipation is . The wire is then cut into two equal halves and a potential of is applied across the length of each half. The total power dissipation across two wires is . The ratio is . The value of is ___________.
Step-by-Step Verified Solution
Let's analyze the initial situation where the potential is applied across the entire length of the wire with resistance .
The power dissipation, , can be calculated using the formula:
Now, let's consider the case where the wire is cut into two equal halves. Each half will have half the original resistance, . The potential is applied across the length of each half.
For each half of the wire, the power dissipation, , can be calculated using the formula:
Since there are two halves of the wire, the total power dissipation across the two wires, , is:
Now, let's find the ratio :
Comparing this to the given ratio , we have:
So, .
Squaring both sides, we get:
The value of is 16.
The power dissipation, , can be calculated using the formula:
Now, let's consider the case where the wire is cut into two equal halves. Each half will have half the original resistance, . The potential is applied across the length of each half.
For each half of the wire, the power dissipation, , can be calculated using the formula:
Since there are two halves of the wire, the total power dissipation across the two wires, , is:
Now, let's find the ratio :
Comparing this to the given ratio , we have:
So, .
Squaring both sides, we get:
The value of is 16.