Calculate the "mean force" during acceleration

What you need:

• Pencil and paper
• Basic knowledge of mechanics
• some time and patience

Force and acceleration - the connection

1. If a body is accelerated, this change in movement always has a cause, namely a force that causes it.
2. There is a very simple connection, so to speak, the basic equation of mechanicswhich already goes back to Newtons: force = mass times acceleration.
3. In formulas: F = m x a; where F is the acting force in Newtons (N), m is the mass (colloquially: the weight) of the Body in kilograms (kg) and a is the acceleration in the unit of meters per square second (m / s²).
4. So if you know the acceleration a that was given to a body of mass m, you can use it during this Calculate the force acting on the acceleration process (more precisely "average force" - this could vary slightly).
5. Note: The definition of the force unit Newton is actually based on an acceleration process (and this basic law). Exactly one force F = 1 N acts when a body of mass m = 1 kg has an acceleration of a = 1 m / s² experiences (or better understandable: accelerated from rest to a speed of 1 m / s in 1 second will).
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Physics - use of physical quantities

Do you know the original meter or the original kilogram that is now in a museum in Paris ...

The mean force - a calculated example

1. Suppose you accelerated a car with the mass m = 800 kg from zero to one hundred. If it lasted 15 seconds, what was the mean force at work during this process?
2. An acceleration from zero to one hundred is of course a somewhat sloppy expression for the fact that the car was accelerated from a speed v = 0 to a speed v = 100 km / h.
3. First you have to convert the final speed v = 100 km / h = 27.78 m / s (reminder: 3.6).
4. Calculate the acceleration a = v / t = 27.78 m / s / 15 s = 1.852 m / s²
5. Calculate the mean effective force F = m x a = 800 kg x 1.852 m / s² = 1482 N (rounded).
6. Note: For such tasks it is always beneficial to convert all quantities into the basic units (i.e. km / h in m / s, g in kg, h in s etc.), then you do not need to worry about the correct units when calculating the force. It automatically comes out Newtons.
7. Incidentally, this applies to all physical formulas: If you always calculate in the basic units, the basic units come out again.