Physics n00b Problem - Power Conversion

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Power conversion relates to the relationship between voltage (V), current (I), and power (P) in electrical circuits, defined by the equation P=IV. For a torch bulb rated at 3V and 0.5A, the power can be calculated by multiplying these values, resulting in 1.5 watts. The units confirm that voltage is in joules per coulomb, current in coulombs per second, leading to power measured in watts (joules per second). Understanding these conversions is crucial for accurately determining power usage in electrical devices. This knowledge is essential for anyone working with electrical circuits.
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Power Conversion (Amps & Voltage)

What exactly is Power Conversion in relation to Voltage and Current?
 
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If you mean, what's the power in a circuit, then the equation is:

P=IV ,where P is power, I is current, and V is voltage.

Using V=IR, you can convert that to whatever you need.
 
Well the question I have is as follows:

"A torch bulb has 3V; 0.5A written on the packet.

Calculate the power conversion for the bulb in normal use."


So do I need to use the formula - see I'm unsure with the units. Would the answer therefore be 1.5 something?
 
Can Anyone Help?
 
V is measured in J/C, I in C/s, so IV in (J/C)(C/s)=J/s=W or Watts.
 
k thanks alot
 

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