1. Newton’s Second Law of Motion
Force, Mass, and Acceleration

2. *Remember
The net force shows whether the forces on an object are balanced or unbalanced.
Unbalanced forces produce a change in motion (acceleration).
Force is measured in Newtons (N).

3. Speed Speed - is the distance an object travels per unit of time.
SI unit for speed is meters per second (m/s).

4. Velocity
Velocity - is the speed of an object in a particular direction.
The SI unit for velocity is m/s + direction.

5. Acceleration Acceleration is the rate at which velocity changes.
SI unit for acceleration is m/s/s or m/s².

6. Acceleration continued
Acceleration is always caused by a force (a push or a pull on something).

7. Positive & Negative Acceleration
Speeding up; is also called accelerating.
Slowing down; is also called decelerating or negative acceleration.

8. Newton’s 2nd Law of Motion
Newton’s Second Law states that the net force is equal to the acceleration times the mass of the object (F=ma).

9. Newton’s 2nd Law Formula
F=ma
In this equation, a is the acceleration (m/s2), m is the mass (kg), and f is the net force (N).

10. Newton’s 2nd Law of Motion
With any given force:
an object with less mass accelerates quicker.
(i.e. volleyball)
an object with more mass accelerates slower.
(i.e. bowling ball)

12. Calculations, Force
Ex 1: A baseball has a mass of 0.2 kg. If its acceleration is 40 m/s2, what is the net force
on the baseball?
Ex 2: A 6 kg cat accelerates at 1.5 m/s2. Find the net force.
F= ma f = ? m = a =

13. Calculations, Acceleration
Ex 3: Suppose you pull a 10-kg sled so that the net force on the sled is 5 N. What is the acceleration?
Ex 4: A net force of 4,500 N acts on a car with a mass of 1,500 kg. What is the acceleration of the car?
F = ma f = m = a = ?

14. Calculations, Mass
Ex 5: A basketball is thrown with a net force of 9 N and accelerates at 1.5 m/s2, what is the mass of the basketball?
Ex 6: An object acted on by a force of 3.6 N has an acceleration of 1.2 m/s2. What is the mass of the object?
F = ma f = m = ? a =