Question

What is the power dissipated when a current of 5 mA flows through a resistance of 20k ohms?

Answer 1

$\huge{\underline{\underline{\red{\mathfrak{AnSwEr :}}}}}$

Given :

• Current (I) = 5 mA = 0.005 A
• Resistance (R) = 20kΩ = 20000 Ω

____________________

To Find :

• Power dissipated

____________________

Solution :

$\large \star {\boxed{\sf{V \: = \: IR}}} \\ \\ \implies {\sf{V = 0.005 \: \times \: 20000}} \\ \\ \implies {\sf{V \: = \: 100}} \\ \\ \implies {\sf{Potential \: Difference \: (V) \: = \: 100 \: V}}$

___________________________

Now use Formula for Power :

$\large \star {\boxed{\sf{P \: = \: VI}}} \\ \\ \implies {\sf{P \: = \: 100 \: \times \: 0.005}} \\ \\ \implies {\sf{P \: = \: 0.5}}$

✯ Power is 0.5 W

Answer 2

Answer:

0.5 watts

Explanation:

given that current is 5 mA

so first convert it to amphere

so for that 5 ma = 5/1000 = 0.005 A

on applying ohms law

v =ir

v = 0.005 × 20,000 (20k )

v= 100 ohms

now to find power dissipated or to find heat

p = vi

p = 100× 0.005

p= 0.5

hence the power dissipated when a 5 ma current flows through 20k omh resistor is 0.5 watts