Car Speed for 1kW Home Power Usage

AI Thread Summary
The discussion centers on calculating the speed of a car based on the energy consumption of a typical house, which is 1 kW over 1.2 minutes. The energy consumed by the house is determined using the formula Energy = Power * time, resulting in 120 joules. To find the car's speed, the relationship between kinetic energy and mass is applied, using the equation Kinetic Energy = mv²/2. Clarification is provided that the house consumes energy at a rate of 1 kW rather than implying a total consumption of 1 kWh. The focus remains on deriving the car's speed from the calculated energy.
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Homework Statement


The power consumption by a typical house is 1 kW. If the kinetic energy of a car (mass 130 kg) is equal to the total energy used by the house in 1.2 minute, what is the car’s speed?

Homework Equations


P=W/t
P=Fv
P:Power

The Attempt at a Solution


I converted 1kW to 1000 Watts and 1.2 minutes to 72 seconds and put it into the first equation but don't know how to get F for the second equation.
 
Last edited:
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Consider:

Energy = Power * time

and

Kinetic Energy = mv2/2
 
Do you mean to say that the power consumed by a typical house is 1 kWh?
 
It is better to say that the house consumes energy at the rate of 1kW. Exactly like the wattage rating on a light bulb. If the house is "on" for 1.2 minutes then you can determine the energy consumed by the house during this interval by:

Energy = Power * time
 

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