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Emf and internal resistance ..may 2018 examss!!!!!!!!! watch

1. We usually assume that ammeters have negligible resistance and voltmeters have
infinite resistance.
The determination of ε and r is not affected by using an ammeter with non-negligible
resistance but is affected by using a voltmeter with a low resistance.
Explain why.(4)
THE MARKING SCHEME SAYS
Ammeter explanation:
If ammeter has resistance, current decreased
but doesn’t affect the determination because current through cell/r is
measured
Or doesn’t affect the determination because the voltmeter measures the
terminal p.d. for that current
OR
The resistance of the ammeter contributes to the load/circuit/total
resistance
Values of p.d. corresponding to given values of current will be
unchanged
Voltmeter explanation:
If voltmeter has smaller resistance it would draw current
measured current not current through cell/r
2. (Original post by maryam1234567)
we usually assume that ammeters have negligible resistance and voltmeters have
infinite resistance.
The determination of ε and r is not affected by using an ammeter with non-negligible
resistance but is affected by using a voltmeter with a low resistance.
Explain why.(4)
the marking scheme says
ammeter explanation:
If ammeter has resistance, current decreased
but doesn’t affect the determination because current through cell/r is
measured
or doesn’t affect the determination because the voltmeter measures the
terminal p.d. For that current
or
the resistance of the ammeter contributes to the load/circuit/total
resistance
values of p.d. Corresponding to given values of current will be
unchanged
voltmeter explanation:
If voltmeter has smaller resistance it would draw current
measured current not current through cell/r
3. Which topic is this
Which topic is this
ITS Q17 (b)
of the year JUNE 2013 IAL 6PHO2/01
IF U KNOW IT THEN PLEASE GUIDE ME!!
5. (Original post by MARYAM1234567)
ITS Q17 (b)
of the year JUNE 2013 IAL 6PHO2/01
IF U KNOW IT THEN PLEASE GUIDE ME!!
Apologies!
Which topic is this
This is basically about resistance in battery and the total energy stored in a battery
Apologies!
check with someone and let me know ASAP!!!

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