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physics acceleration resultant forces question

a 1500kg car accelerates at 1.5m/s^2 along a horizontal road.If the frictional forces acting against the car's motion total 1000N, what driving force is exerted on the road by the car's wheels?

pls help
I used f=ma to give total force as 2250N and subtracted 1000(frictional force) from this to give me 1250N as a driving force.
However this answer is wrong and I don't know what I am doing wrong.
Original post by M.H4kim
a 1500kg car accelerates at 1.5m/s^2 along a horizontal road.If the frictional forces acting against the car's motion total 1000N, what driving force is exerted on the road by the car's wheels?

pls help
I used f=ma to give total force as 2250N and subtracted 1000(frictional force) from this to give me 1250N as a driving force.
However this answer is wrong and I don't know what I am doing wrong.

Why have you subtracted 1000?

Write out the equation of motion properly
Reply 2
Original post by Muttley79
Why have you subtracted 1000?

Write out the equation of motion properly

F=ma?
Original post by M.H4kim
F=ma?

Yes and what is 'F' ie the nett force? Write out the equation in full
Original post by rose.clm
you

EDIT your post - you are breaking forum rules by giving an answer and you aren't helping the OP understand
Reply 5
Original post by rose.clm
you would add on the 1000 frictional force, as the 2250 is the EXTRA force that is required to accelerate.

I still don't get why u add 2250 and 1000
Reply 6
Original post by M.H4kim
I still don't get why u add 2250 and 1000

because it is asking for just the driving force. Not the sum of the frictional forces and the driving force
Original post by M.H4kim
because it is asking for just the driving force. Not the sum of the frictional forces and the driving force

F is the nett forces acting on the car which is what??? Write down ALL the forces
(edited 2 years ago)
Original post by Muttley79
EDIT your post - you are breaking forum rules by giving an answer and you aren't helping the OP understand

ahh sorry I didn't know.
Original post by M.H4kim
I still don't get why u add 2250 and 1000

HAve you sorted this out now?

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