[M2] - Edexcel Jan '03 - Question 2Watch

This discussion is closed.
#1
Having a problem with this... my answer seems to be out by a tenth

The question is as follows:

A car of mass 1000 kg is moving along a straight horizontal road with a constant acceleration of f ms^2. The resistance to motion is modelled as a constant force of magnitude 1200 N. When the car is travelling at 12 ms^1, the power generated by the engine of the car is 24 kW.

(a) Calculate the value of f.
This is my working for it:

Power = Driving Force * Speed

=> 24000 = F * 12
=> F = 2000

So Force output by car is 2000 N

Then by N2L:

Force = Mass * Acceleration

=> 2000 - 1200 = 1000a
=> 0.8 = a

So acceleration of the car is 0.8 ms^2

Now in the answers it says its 0.08

So where have I gone wrong?

MdSalih
0
14 years ago
#2
(Original post by MdSalih)
Having a problem with this... my answer seems to be out by a tenth

The question is as follows:

This is my working for it:

Power = Driving Force * Speed

=> 24000 = F * 12
=> F = 2000

So Force output by car is 2000 N

Then by N2L:

Force = Mass * Acceleration

=> 2000 - 1200 = 1000a
=> 0.8 = a

So acceleration of the car is 0.8 ms^2

Now in the answers it says its 0.08

So where have I gone wrong?

MdSalih
Looks Ok at first glance.

Aitch
0
14 years ago
#3
(Original post by MdSalih)
Having a problem with this... my answer seems to be out by a tenth

The question is as follows:

This is my working for it:

Power = Driving Force * Speed

=> 24000 = F * 12
=> F = 2000

So Force output by car is 2000 N

Then by N2L:

Force = Mass * Acceleration

=> 2000 - 1200 = 1000a
=> 0.8 = a

So acceleration of the car is 0.8 ms^2

Now in the answers it says its 0.08

So where have I gone wrong?

MdSalih
Absolutely fine
Either the answer is wrong, the question is wrong Or maybe maths doesnt work
0
X
new posts

Latest
My Feed

Oops, nobody has postedin the last few hours.

Why not re-start the conversation?

see more

See more of what you like onThe Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

University open days

• University of East Anglia
All Departments Open 13:00-17:00. Find out more about our diverse range of subject areas and career progression in the Arts & Humanities, Social Sciences, Medicine & Health Sciences, and the Sciences. Postgraduate
Wed, 30 Jan '19
• Aston University
Wed, 30 Jan '19
• Solent University
Sat, 2 Feb '19

Poll

Join the discussion

Remain (846)
80.65%
Leave (203)
19.35%