A copper wire has cross sectional area 4×10-6m2 and resistivity of 1.6×10-8ohmmeter. Calculate the length of the wire to make its resistance10ohms. By how much does the resistance change if the diameter is doubled?
a copper wire of resistivity 1.6x10 raise to the power -8 ohm meter has a cross sectional area of 20x10 raise to the power -4cm square . calculate the length of this wire required to make a 10 ohm coil