Calculating Chemical Energy Needed to Travel 100km: 4.8 N

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To calculate the chemical energy needed for a car to travel 100 km, the user applied the kinetic energy formula E = 1/2 mv^2, resulting in 481,258.26 J for a car mass of 1953 kg and a velocity of 22.2 m/s. They then used the work formula W = F * D to derive a force of 4.8 N. However, there was confusion regarding the assignment's requirements, as it involved coasting after reaching 80 km/h rather than calculating total energy for the distance. The discussion highlights the importance of understanding the context of the problem, including factors like surface type and efficiency. Clarification on the assignment's intent is needed for accurate calculations.
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Did I do this right??

How much chemical energy would be consumed to travel 100km?
* Assuming 100% efficency *
Mass of car = 1953 kg
velocity = 22.2m/s

Here is what I did
E = 1/2 m v^2
E = 1/2 * 1953 * 22.2^2
E = 481258.26 J

Now I plugged the Energy I got into this formula
W = F * D
481258.26 = f * 100,000
Divide both sides by 100,000
F = 4.8 N

Ok so that's the work that I have done. I don't think I was supposed to find the force. What is chemical energy. I thought I did it wrong becasue I thought I was supposed to use E = 1/2mv^2 and add the answer to the W =Fd answer.
So I am kinda lost... Any help is appreciated!
 
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Are you traveling on gravel/asphalt/sand/water? Are you repeating the question exactly as it appears in the assignment? It doesn't make sense.
 
Last edited:
Asphalt, The assignment was to get the car up to 80km/h then shift it into neutral and see how far you coast.

here is someother info you might need
mu = 0.0251
 
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