Posts Tagged ‘efficiency’

The experiment was ‘Determining the efficiency of energy conversion of boiling water in an electric kettle‘.

The method/system -

1. Weigh accurately 1000g of water and pour into the kettle provided.
2. Switch on to boil and start the timer. Time how long it takes for the water to boil and record your result.

I calculated the amount of energy used to make the water boil to be -334.4 KJ.

I calculated the ‘efficiency’ of energy inter-conversion of the system to be 77.4%.

Evaluate the experiment above, identifying energy loss and errors, and access their effect on the efficiency?

THANK YOU!

Additional Reference Information

The experiment was ‘Determining the efficiency of energy conversion of boiling water in an electric kettle‘.

The method/system -

1. Weigh accurately 1000g of water and pour into the kettle provided.
2. Switch on to boil and start the timer. Time how long it takes for the water to boil and record your result.

I calculated the amount of energy used to make the water boil to be -334.4 KJ.

I calculated the ‘efficiency’ of energy inter-conversion of the system to be 77.4%.

Evaluate the experiment above, identifying energy loss and errors, and access their effect on the efficiency?

THANK YOU!

Additional Reference Information

The experiment was ‘Determining the efficiency of energy conversion of boiling water in an electric kettle‘.

The method/system -

1. Weigh accurately 1000g of water and pour into the kettle provided.
2. Switch on to boil and start the timer. Time how long it takes for the water to boil and record your result.

I calculated the amount of energy used to make the water boil to be -334.4 KJ.

I calculated the ‘efficiency’ of energy inter-conversion of the system to be 77.4%.

Evaluate the experiment above, identifying energy loss and errors, and access their effect on the efficiency?

THANK YOU!

Additional Reference Information

I did an experiment in which I had to boil water in an electric kettle.

The two points below are sources of error of the experiment that I described above.

1) Variation in power usage rate. It isn’t always in steady state.
2) Variation in the background atmospheric pressure, which depends on many weather factors. This effects the boiling temperature, which is why you need to cook boiled food longer at high altitude.

My calculated efficiency is 77.4%. Would the points above lower it, raise it, or have no effect on it?

THANK YOU!

Additional Reference Information

In heating a kettle of water on an electric stove, 3.34 x 10 (to the power of)3 J of thermal energy was provided by the element of the stove. Yet, the water in the kettle gained only 5.95 x 10 (to the power of)2 J of thermal energy. Determine the percent efficiency of the electric element in heating the kettle of water.

Additional Reference Information