Kinda weird

[kenhung123]

How do I do this?

A trailer of mass 300kg is being towed on a level road by a car mass 1000kg. There is a constant retarding force, due to air resistance and friction, of 90N on the trailer, and 400N on the car. The vehicles are travelling at a constant speed.
What is the:
a. value of the tension, T, in the towbar?
b. magnitude of the force driving the car?
c. How far will the car and trailer travel before coming to rest?

[/0]

Draw free body diagrams for each vehicle.
(By the way it was not necessary to draw the vertical forces - which is especially annoying when you have wheels...
, , but I included them for completeness)

a) Use on the trailer.

b) Use on the car.

c) Until the fuel runs out.

Nah, the question is worded badly. Probably means after the engine is turned off. Only thing is it's missing the speed...

Oh well, total retarding force (on the whole system) is

Then use

Solving should give

[kenhung123]

I'm assuming c means distance but since a=0 wouldn't distance be zero?

[/0]

Ah crap, read it wrong. Yeah but they are travelling at constant speed so they shouldn't even slow down.

[superflya]

constant retarding force & constand speed ? wtf

[/0]

The driving force opposes the retarding force exactly so that it stays at constant speed.

[superflya]

lol -.- ahhhk