Categories
Ask Physics change in resistance Current Electricity stretching

Change in resistance due to stretching a wire

“There is a wire whose resistance is R. it is streched, and its length gets increased to 2%. find new resistance.” – Knishka Agrawal asked Answer: The resistivity does not change due to stretching, but the length and area of cross section changes; but the volume remains constant. Therefore, resistance changes which can be calculated …Read the full post

Categories
Ohm's law percentage change Physics Homework

If a Cu wire is stretched to make it 0.1% longer , the %age change in its resistance is ?

When stretched, the volume remains constant. So, A1l1=A2l2 Original resistance R1= rl1/A1 Final Resistance R2= rl2/A2 Percentage change in resistance = (R2-R1)x100/(R1) Substitute the values and try to get the answer

Categories
Class X Physics

Electricity – Class X CBSE

Some important points to remember The resistance of a conductor does not change when the current through it is changed or the voltage across it is changed. When current is changed, the voltage across it is also changed so that the ratio V/I = R The value of resistance changes if the dimensions (length or […]

Categories
Answers

Resistance and Resistivity

Simran Asked “Two wires A and B of equal lengths,different cross-sectional areas and made of same metal a)name the property which is same for both the wires. b)name the property which is different for both the wires” Answer: Since both the wires are of same metal, the resistivity will be same for both whereas since […]