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प्रश्न
An electric circuit consisting of a 0.5 m long nichrome wire XY, an ammeter, a voltmeter, four cells of 1.5 V each and a plug key was set up.
Following graph was plotted between V and I values:
What would be the values of `V/I` rations when the potential difference is 0.8 V, 1.2 V and 1.6 V respectively?
What conclusion do you draw from these values?
What is the resistance of the wire?
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उत्तर
When potential difference = 0.8 V, current = 0.32 A.
`V/I=0.8/0.32`
`V/I = 2.5`
When potential difference = 1.2 V, current = 4.8 A.
`V/I= 12/48`
`V/I=2.5`
When/ /potential difference = 1.6 V, current = 6.4 A.
`V/I= 1.6/6.4 `
`V/I =2.5`h V-I graph is a straight line with a constant slope of 2.5.
The resistance of the wire is 2.5 Ω.
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