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Physics: Post your doubts here!

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A student uses a digital ammeter to measure a current. The reading of the ammeter is found to
fluctuate between 1.98 A and 2.02 A.

The manufacturer of the ammeter states that any reading has a systematic uncertainty of ± 1 %.

Which value of current should be quoted by the student?
A (2.00 ± 0.01) A
B (2.00 ± 0.02) A
C (2.00 ± 0.03) A
D (2.00 ± 0.04) A

How is the answer D?
 
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let the left loop be called as A and the right loop as B(loop of the resistors)
For loop A, total of resist. is 15ohm and in other loop i.e. B is also 15ohm
But both of them are in parallel that why resistance of the circit as a whole is 15/2 (1/15+1/15=2/15 and its inverse)
 
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3W3er7E.jpg
Can I get help with this question please?
 
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using V=IR
2=I(15/2)
=> I=4/15
Dividing current equally, current in A is 2/15 and in B is 2/15
Now in a X is attached to end of 1 resistor, hence in A again using V=IR we getV=2/15*5=2/3
Now subtracting 2-2/3 gives 4/3 is the voltage at X
now, Y is attached to end of second resistor in loop B, hence, V at Y=2/15*10=4/3
Subtracting 4/3 from 2 gives 2/3
Now V at X - Vat Y= 4/3-2/3 =2/3
 
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