1. FORCES Test on Wednesday speed DvT Acceleration Forces

2. The Equation F=ma Force equals mass times acceleration Force Mass Acceleration

3. Logic Since all of the variables are directly related, then a change in one DIRECTLY results in a change in another F=ma If my force goes down, then my acceleration (or mass) has to go down too.

4. Think If mass increases, what should happen to acceleration? If acceleration decreases, what should happen to force? If force increases, what should happen to acceleration? If mass decreases, what should happen to force?

5. Problems When our mass is in kg (kilograms) and our acceleration is in m/s 2 (meters per second squared) then our force’s units will be: kg(m/s 2 )  Newton (N)

6. Examples Timmy hits the gas petal of his car and it provides 5000 N of force onto the road. If his car and he have a mass of 1850 kg, then how quickly do they accelerate? How much mass does a ball have that accelerates at 20 m/s 2 when 15 N of force is applied to it?

7. You Try How much force is applied to an 18-wheeler with a mass of 12,000 kg if it accelerates forward at 3.1 m/s 2 ? You push a box that on the ground forward with 50 N of force. If the box accelerates forward at 0.4 m/s 2, how much mass does it have?

8. Acceleration VS Velocity Remember! Acceleration and velocity are different! Therefore, if an object experiences an unbalanced force it should ACCELERATE. What if you push something and it just moves a constant speed? Forces are BALANCED. Engine Friction