Finding power consumed by an electric razor

In summary, the tourist used the equation P=IV to find the current for the razor at 120 V and then used that number to find the power at 220 V. However, the resistance of the razor remains constant.
  • #1
kohlzie122
2
0
A tourist takes his 21 W, 120 V AC razor to Europe, finds a special adapter, and plugs it into 220 V AC. What power does the razor consume as it goes up in smoke?


P=IV=deltaVsquared/R


attempt at solution:
I used P=IV for 120 V to find the current, and using that number, plugged the numbers into the equation for 220V. The hint for the problem says that the resistance doesn't change for the razor in Europe... but I don't know how that helps. I feel like I'm missing something very easy but I'm stuck.
 
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  • #2
Welcome to the PF. The key here is that the resistance doesn't change. I don't think you want to write:

[tex]P = \frac{\Delta {V^2}}{R}[/tex]

Instead, write two equations, one for the US and one for smokey Europe...
 
Last edited:
  • #3
Oh man that was easy.. I'm a little embarrassed. Thanks for the help!
 
  • #4
Hey seems like you guys figured it out. Can you help me. I'm stuck on the same question and I don't know what to do.
 

1. How do you measure the power consumed by an electric razor?

The power consumed by an electric razor can be measured by using a watt meter, which measures the electrical current flowing through the razor and the voltage of the power source.

2. What units are used to measure power consumption?

The unit used to measure power consumption is watts (W), which is a measure of the rate at which energy is being used.

3. Can the power consumption of an electric razor vary?

Yes, the power consumption of an electric razor can vary depending on factors such as the type of razor, its age, and the length and thickness of the hair being shaved.

4. How does the power consumption of an electric razor compare to a manual razor?

An electric razor typically consumes more power than a manual razor, which does not require electricity to operate. However, the amount of power consumed by an electric razor is relatively small and can vary depending on usage.

5. Can the power consumption of an electric razor be reduced?

Yes, the power consumption of an electric razor can be reduced by using energy-efficient models, unplugging the razor when not in use, and following proper maintenance and cleaning procedures to keep the razor running smoothly.

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