1. Terminal Velocity
Think before you jump

2. Disregarding air friction, the net force is the weight of the object.
Weight =mg

3. Disregarding air friction
All objects in free fall near the earth’s surface accelerate at a constant rate.

4. Taking air friction into account
Weight=mg
Air friction depends on speed, surface area, shape of object, viscosity of fluid.

5. At terminal velocity, the net force equals zero.
Friction= 730 Newtons
Weight = 730 Newtons
Therefore, the acceleration is zero.

6. Acceleration is the rate at which an object changes its velocity.

7. Terminal velocity occurs when the friction up equals the weight down.
a = 0 m/s2
weight
v = constant
The acceleration will be zero and the velocity will be constant.

8. At what rate is the top sky diver advancing on the lower diver?
V= 200 mi/hr
V = 120 mi/hr

9. Direct proportion example
Acceleration is directly proportional to the net force applied to the object.

10. Inverse proportion example
Acceleration is inversely proportional to the objects mass.

11. What will happen to acceleration if the object’s mass is doubled?
The acceleration will be 1/2 of its original value.

12. What is the net force on a 1 N apple when you hold it at rest in your hand?
Net force is zero, and therefore the apple does not accelerate.

13. What is the net force if you let go of the apple?
1 Newton

14. Can the velocity of an object change while it maintains a constant acceleration?
Yes, Yes, a thousand times yes.

15. A dropped book accelerates at a constant rate of 10 m/s2 down if we disregard air friction.

16. Velocity is changing but acceleration is a constant 10 m/s2 down.
V=10 m/s
V=10 m/s
V=20 m/s
V=30 m/s