Hpw would you do this problem?

Question

a 1,000kg car accelerates uniformly to double its speed from 36.0km/h in 5.00 s.

a)what is the net force acted on the car?

I'm not sure but is this how you do it?

acceleration= change of velocity
______________
Time


72-36km/h
_________ = 7.2 acceleration


force= 1,000 x 7.2

7,200 net force
5.0s

Answer 1

Force is mass * acceleration.

So you first need to find the acceleration, a.

a = (v2 - v1)/(t2 - t1) = (2*36 - 36)/5 = 36 / 5 = 7.2 km / h / s.

Yikes!!! We need to convert our answer to standard units.

Since 1000 m = 1 km and 3600 s = 1 hr....

7.2 * 1000 / 3600 = 2 m / s²


To find the force....

F = 1000 * 2 = 2000 N

Answer 2

You know it's initial speed was 36 kph, it's final speed is 72 kph, and this took 5 seconds. Use v = u + a*t to find the acceleration.

36 kph = 10 m/s
72 kph = 20 m/s

20 = 10 + a*5

a = 10/5 = 2 m/s^2

Now use Newton's Law of F = ma = 1000*2 = 2,000 N

Answer 3

well i dont remember physics. But what is the formula for calculating force? Use that and you should get the answer. Remember to check and make sure ur units are the same.

Answer 4

the SI unit is in m/s, so you have to convert to m/s

36km/hr = 10m/s

Initial velocity is 10m/s
Final velocity is 20m/s

find acceleration
Vf = at + Vi
20m/s = a(5s) + 10m/s
10m/s = a(5s)
a = 2m/s^2

F = ma
F = (1000kg)(2m/s^2)
F = 2000N