If force=mass x accleration than how do you get each one into numbers you can multiply together?

Question

FOR EXAMPLE A CAR WEIGHS 2500 LBS AND IS TRAVELING 65 MPH HOW DO YOU FIGURE OUT ITS FORCE

Answer 1

The example you gave doesn't have enough information to compute the force on the wheels. In a frictionless world, there would be zero force if the car is traveling at a constant speed on level ground.

In order to compute the force you need to know the resistance to forward motion which is the force due to air resistance, and the rolling friction of the car.

j

Answer 2

As was pointed out above, the example you give probably doesn't have force since you don't mention friction. Instead of velocity, you need to specify acceleration.

I think I know what's confusing you tho. If the car's mass is 1000 kg and the acceleration is 10 m/s^2, what's the force causing the acceleration?

F = m*a
F - 1000 kg*10 m/s^2 = 10,000 kg*m/s^2
But you're supposed to give the answser in Newtons!

Well a Newton is defined as 1 kg*m/s^2. So for my problem,
F = 10,000 Newtons

Answer 3

Convert the lbs into Kilograms and the MPH into meters/second. Then multiply the 2 numbers and that is ur force

Answer 4

The standard unit of force is the Newton. To get the number in this unit, you need to convert the mass to kg, and the speed to metres per second. To help you, 1kg = 2.2lbs, and 1 mile is 1609 metres. I don't have a calculator on me, so you'll have to do that bit!