How Do You Calculate the Net Force on an Accelerating Car?

[discosucks]

Homework Statement

An 850 kg car accelerates uniformly from rest to 33 m/s in a distance of 120 m. What is
the magnitude of the net force acting on the car?

Homework Equations

F = ma

dynamic equations

The Attempt at a Solution

So i think i have this one sorted but just posting to see iv got it right .

Seeing as i need acceleration to find the force i have to find it using the info i have so

a= ?
s= 120
v = 33
u = 0
t = not needed .

v^2=u^2+2as

(33)^2 = 0 + 2(a)120

1089 = 240a

4.5375 = a

4.5375 m/s^2

F = ma

850 x 4.5375

3856.875 N

 

[NascentOxygen]

v^2=u^2+2as

Method looks right. (I haven't checked your arithmetic.)

 

[Maged Saeed]

It seems right ,,.

 

[discosucks]

Great! thanks lads! this site rocks! need to find a similar one for chemistry and biology haha

 

[HalfLostAndSearching]

I can confirm that your solution is correct. The magnitude of the net force acting on the car is approximately 3856.875 N. This calculation is based on the equation F=ma, where F is the net force, m is the mass of the car, and a is the acceleration. In this case, the acceleration is 4.5375 m/s^2, which is obtained by using the formula v^2=u^2+2as, where v is the final velocity, u is the initial velocity, and s is the distance traveled. By substituting the given values and solving for a, we can then calculate the net force using the mass of the car. This is a good demonstration of how the dynamic equations can be used to solve real-world problems in physics.