Calculating Average Retarding Force on Car

[lim]

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 ?

 

[Astronuc]

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

 

[lim]

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.