Calculating Average Retarding Force on Car

AI Thread Summary
To calculate the average retarding force on a car that does 6.48E+4 J of work while traveling 2.92 km, the formula F = w/d is used. The work done is converted to 64800 J and the distance to 2920 m. The correct calculation shows that the average retarding force is 22.2 N, not 2.22 N as initially attempted. Attention to unit conversions and scientific notation is crucial for accurate results. Proper understanding of these concepts leads to the correct determination of the retarding force.
lim
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Homework Statement



A car does 6.48E+4 J of work in traveling 2.92 km at constant speed. What was the average retarding force (from all sources) acting on the car?
22.2 N

Homework Equations




F= w/d

The Attempt at a Solution



F= w/d

6.48/ 2.92= 2.22 N ?
 
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lim said:

Homework Statement



A car does 6.48E+4 J of work in traveling 2.92 km at constant speed. What was the average retarding force (from all sources) acting on the car?
22.2 N

Homework Equations



F= w/d

The Attempt at a Solution



F= w/d

6.48/ 2.92= 2.22 N ?
Please pay attention to the units and exponent or powers of 10.

6.48E+4 J = 64800 J

2.92 km = 2920 m

1 J = 1 N-m or 1 N = 1 J/m = 1 kg-m/s2
 
oooh, I had a feeling it had something to do with unit conversions, but the E threw me off. I guess I'm used to seeing 10^x. Thanks for pointing it out Astronuc.
 

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