Question

. If 50 coulombs of charge is flowing through a wire having potential difference of 400 mV, then work done by resistor will be​

Answer 1

Answer :

• Work done by the resistor is 20 J

Explanation :

Given :

• No. of coulombs flowing in the circuit, n = 50
• Potential difference of the circuit, V = 400 mV or 0.4 V

To find :

• Work done by the resistor, W = ?

Knowledge required :

By definition, Work Done by a circuit is the product of the potential difference , charge and time of flowing of the charges,i.e,

⠀⠀⠀⠀⠀⠀⠀⠀⠀W = V × I × t⠀

Where,

• W = Work done
• V = Potential difference
• I = Current
• t = Time Taken

But we know that the product of Current and the time taken for flow of current gives the no. of charges.i.e,

⠀⠀⠀⠀⠀⠀⠀⠀⠀n = I × t⠀

Where,

• n = No. of charges
• I = Current
• t = Time Taken

So by substituting it in the equation for work done, we get :

⠀⠀=> W = V × I × t

⠀⠀=> W = V × n

⠀⠀⠀⠀⠀⠀∴ W = V × n

Hence the formula for work done is V × n.

Solution :

By using the formula for work done and substituting the values in it, we get :

⠀⠀=> W = 0.4 × 50

⠀⠀=> W = 4/10 × 50

⠀⠀=> W = 4 × 5

⠀⠀=> W = 20

⠀⠀⠀⠀⠀⠀∴ W = 20 J

Therefore,

• Work done by the resistor, W = 20 J

Answer 2

Answer:

Explanation:

Given,

Number of coulombs, n = 50

Potential difference, V = 400 mV or 0.4 V

To Find,

Work done, W = ?

Formula to be used,

W = V × n

Solution,

Putting all the values, we get

W = V × n

⇒ W = 0.4 × 50

⇒ W = 4/10 × 50

⇒ W = 4 × 5

⇒ W = 20 J

Hence, the work done by resistor will be​  20 J.