Calculating Power and Resistance of a Domestic Bulb with 0.25A and 12V

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A current of 0.25A flowing through a bulb at 12V results in a power output of 3W, calculated using the formula power equals current times voltage. To find the resistance of the bulb, Ohm's Law can be applied, where voltage equals current times resistance (V = IR). Rearranging this formula gives resistance as voltage divided by current, which in this case is 12V divided by 0.25A, resulting in a resistance of 48 ohms. The discussion emphasizes understanding the relationship between power, current, voltage, and resistance in electrical circuits. Mastery of these concepts is essential for success in physics.
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A current of 0.25A flows through a bulb when a voltage of 12V is applied across it. Calculate the power and resistance of the bulb.

please show working out
 
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Welcome to PF!

Hi hgo0! Welcome to PF! :wink:

Show us what you've tried, and where you're stuck, and then we'll know how to help! :smile:
 
0.25A x 12V = 3W

i don't know how to get the resistance or if I am doing this right :rolleyes:
 
hgo0 said:
0.25A x 12V = 3W

Hi hgo0! :smile:

That's right: amps times volts = watts (or current times voltage = power).
i don't know how to get the resistance or if I am doing this right :rolleyes:

Have you done Ohm's Law (or Kirchhoff's rules ) ? If not, look them up.

V = IR (or potential difference = voltage = current times resistance). :wink:
 
kk thanks a lot I'm new to physics (first year) and failing soo i need all the help i can get :biggrin:
 

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