How Long to Melt an Ice Cube in a Microwave with 104 Watts?

AI Thread Summary
To determine the time required to melt an ice cube in a microwave with a power output of 104 watts, the formula t = J/W is applied, where J is the energy needed (32165 J) and W is the power (104 W). The calculation yields a time of approximately 309.3 seconds. The conversion of watts to joules per second is confirmed, as 1 watt equals 1 joule per second. This method effectively calculates the duration needed for the ice cube to melt. The discussion emphasizes the importance of correctly applying the formula for accurate results.
Cassie
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An ice cube is placed in a microwave oven. Suppose the oven delivers 104 W of power to the ice cube and that it takes 32165 J to melt it. How long does it take for the ice cube to melt?


Following my lecture notes and my textbook ... the formula should be t=(J/W), but that isn't giving me the correct answer. Therefore I assume I am missing a step, can anyone help?
 
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What answer did you get?
 
Cassie said:
An ice cube is placed in a microwave oven. Suppose the oven delivers 104 W of power to the ice cube and that it takes 32165 J to melt it. How long does it take for the ice cube to melt?


Following my lecture notes and my textbook ... the formula should be t=(J/W), but that isn't giving me the correct answer. Therefore I assume I am missing a step, can anyone help?

I am getting an answer of 309.3s using your equation which seems correct to me...

1 Watt = 1 J/s so 104Watts=104J/s

Then dividing the energy used to melt the ice by the power output of the microwave.
 

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