Missing gravity and kinetic friction

AI Thread Summary
The calculation of work done on the car during the time interval is based on the change in kinetic energy, yielding a result of approximately 463,953,703.8 joules. The user questions whether they have accounted for gravity and kinetic friction in their calculations. The response confirms the method is correct but raises skepticism about the feasibility of a car with a mass of 75,000 kg achieving such high speeds in a short time. The discussion highlights the importance of considering realistic parameters in physics problems. Overall, the calculations are mathematically sound, but practical considerations may need to be addressed.
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Homework Statement



What is the network done on the car during the time interval?

Mass = 75,000kg
Vi = 0
vf = 111.11m/s^2
t = 2.5s
∆x = 138.8875m


Homework Equations



W= F∆X

∆KE = (1/2)(m)(v)^2

W = ∆KE

The Attempt at a Solution



∆KE = 1/2(75000kg)(111.11m/s)^2
∆KE = 463953703.8j

And since W=∆KE
W = 463953703.8j

Is this right? I am wondering if I am missing gravity and kinetic friction somewhere?

Thanks
 
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Your method of calculation is correct - I did not plug in the numbers to see if you did that part correctly. I cannot help wondering what kind of car has mass 75,000 kg (75 tons) and is able to go from zero to 111 m/s (250 miles per hour) in 2.5 s.
 
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