# Ppl i am just 14 and am tryin to make a car and i am having problems

1. Nov 14, 2009

### saarthak007

ppl i am jus 14 and tryin to make a car
the amount of phsics i no is a bit less
i started calculating
by assuming:-
car weight = 50kg
passenger weight 50 kg
propultion system weight =5okg
total weight =150 kg
speed 20km/h = 5.5m/s
i am taking =5 m/s approx
time taken= 10 sec
acceleration =0.5m/s2
force =150 x 0.5=75 newton
energy =1875juoles = 1.875kj
power = 187.5 watt
my question is that **"how much slope can it move on??"**
coz i dont no cos tan sin

Last edited: Nov 14, 2009
2. Nov 14, 2009

### saarthak007

Re: physics query i am tryin 2 make a car ppl, plz reply

ppl reply i need ur help

3. Nov 14, 2009

### xxChrisxx

Formatting and full comprehensive sentences are your friend.

You need to know the thrust at the wheels.

Found from engine torque * gear ratio * rolling radius.
This will give you the max force available at the wheels.

F = mg sin theta

Run for a range of theta, and you can find the max slope you can get up.
or rearrange or theta and work it out with arcsin (I dont know if you will have learnt that at 14)

Last edited: Nov 14, 2009
4. Nov 17, 2009

### saarthak007

hey can u find it for me i am havin problem

5. Nov 17, 2009

### xxChrisxx

I can't find it for you, I have told you how to find it though.