Answer the following:
- Why are the connections between the resistors in a meter bridge made of thick copper strips?
- Why is it generally preferred to obtain the balance point in the middle of the meter bridge wire?
- Which material is used for the meter bridge wire and why?
CBSE OUTSIDE DELHI - SET 3 2014
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- This is to ensure that the connections do not contribute any extra, unknown, resistances in the circuit.
- This is done to minimize the percentage error in the value of the unknown resistance.
This is done to have a better “ Balancing out” of the effects of any irregularity or non-uniformity in the metre bridge wire.
Alternate Answer
This can help in increasing the senstivity of the metre bridge circuit.
- Manganian/constantan/Nichrome. This material has a low temperature of coefficient of resistance/high reisistivity.
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