NEET 2022
- Exam
- NEET
- Year
- 2022
- Subject
- Physics
- Chapter
- Current Electricity
NEET 2022 · Physics · Current Electricity
A Wheatstone bridge is used to determine the value of unknown...
A Wheatstone bridge is used to determine the value of unknown resistance by adjusting the variable resistance as shown in the figure. For the most precise measurement of , the resistances and
Options
- Ashould be approximately equal and are small
- Bshould be very large and unequal
- Cdo not play any significant role
- Dshould be approximately equal to
Correct answer
A. should be approximately equal and are small
Step-by-step solution
For precise measurement of , value of should be close to . Therefore, resistances and should be equal.
If and are large the current in the galvanometer will be small, and it will be difficult to find the null point. Therefore, and should be small.
If and are large the current in the galvanometer will be small, and it will be difficult to find the null point. Therefore, and should be small.