Is the circuit given below correct? Justify your answer.

 

Write the formula of the relation between resistance and resistivity of an ohmic conductor. A wire of length '$l$' and resistance '$R$' is stretched so that its length is doubled and area of cross-section is halved. How will its resistance change? Justify your answer.

A wire of length '$l$' and resistance '$R$' is stretched so that its length is doubled and area of cross-section is halved. How will its resistivity change? Justify your answer.

What do the following symbol mean in the circuit diagrams?

What do the following symbol mean in the circuit diagrams?

An electric circuit consisting of $0.5 \mathrm{m}$ long nichrome wire $XY,$ an ammeter, a voltmeter, four cells of $1.5 \mathrm{V}$ each and plug key were set-up.

Draw the diagram of this electric circuit to study the relation between potential difference maintained between the points $X$ and $Y$ and electric current flowing through $XY.$

The graph shown is plotted between $V$ and $I$ values. What would be the value of ratio, when potential differences is $0.8 \mathrm{V},$ and $1.2 \mathrm{V}.$ What conclusion can you draw from these values?

State Ohm's law.