Let the resistance of an electrical component remains constant while the potential difference across the two ends of the component decreases to half of its former value. What change will occur in the current through it?

According to Ohm’s law

V = IR

where

The equation can also be written as – 

I = V/R ---- (1)

It is given that the potential difference across two ends of an electric component decreases to half

So, the new potential difference be Vʹ= V/2---- (2)

Resistance remains constant, therefore the new current that is drawn through the electrical component is

Iʹ = Vʹ/R ---- (3)

Substituting the value of V’ from equation (2) in equation (3), we get

I’ = (V/2)/R

I’ = (1/2) (V/R)

Since V/R = I

I’ = (1/2) I

I’ = I/2

Therefore, the amount of current that flows through the electrical component is reduced by half.


Related Questions

  1. What is the necessary condition for a conductor to obey Ohm's Law?
  2. What Is Effective Resistance?
  3. Why is the curve representing Ohm's law linear?
  4. How Do You Find The Resistance Of A Wire?
  5. What are the 3 forms of Ohm's law
  6. How do you find the resistance to Ohm's law?
  7. What Is Ohm's Law Graph?
  8. What are the applications of ohm's law used in daily life?
  9. What are the limitations of Ohm's Law?
  10. Is resistance constant in Ohm's law?
  11. Does Current Increase With Voltage?
  12. Draw a circuit diagram to verify ohm’s law.
  13. Why is the series arrangement not used for domestic circuits?
  14. The resistance R= V/I, where V=100 ± 5.0V and I = 10 ± 0.2A. What is the total error in R?
  15. How many 176 Ω resistors (in parallel) are required to carry 5 A on a 220 V line?

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                          CBSE CLASS XII Previous Year Papers

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