2. What is the formula for constant speed?

3. Symbolically, what is the distance around a circle?

4. What is the formula for the speed if one is moving around in a circle?

5. What is the formula for the centripetal acceleration?

6. What does centripetal mean?

7. What is the formula for centripetal force?

8. A person swings a 0.65 kg rock in an old fashion slingshot around in a vertical circle. The length of the slingshot is 0.85 m. If the person swings the rock around once in 0.55 seconds, determine:
a) The slingshot’s speed
 

b) The slingshot’s tension when the rock is at the bottom of the swing
 

c) The slingshot’s tension when the rock is at the lowest point of the swing
 

9. Suppose the same person swung the rock around horizontally at an angle of 20 degrees below the horizontal.

Draw the free body diagram of the rock in a sling below
 
 
 
 
 
 

 How many forces are in the y?

 Is it moving in the y direction?

 What condition is the y direction in?

 How many forces are in the x direction?

 What part of the circle does the horizontal force point?

 What does the horizontal force equal?

Write an equation in the y direction.

What can you solve for? Solve for it!

Write an equation in the x direction.

Solve for the radius of the circle using Geometry then solve for the velocity of the rock
 

What is the basic formula for work?

What one thing must you remember conceptually about the formula above?

Can work be negative? If so, the force must be what?

If the force is at an angle, and the displacement along the + X: What must you do to the force before you apply the formula?

A man pushes down on a lawnmower with a force of 50 N at 55 degrees above the horizontal along the +x.
a) If the displacement is 6 m, how much work does the man do on the lawnmower?
 
 

Work equals a change in what?

b) If the lawnmower starts from rest, how fast is it moving at the end of the 6 m if its mass is 100 kg?
 
 
 

A crane pulls a 250 kg box 35 m upward with a constant speed in 5.5 seconds.

a) What is the formula and units for Power?

b) What is the force in this case?

c) Solve for Power.
 

What is the formula for potential energy?

What is the formula for kinetic energy?

What is the unit for energy?

Suppose the crane in the problem above has a giant 400 kg ball at the end of a 15 m cable.
If the ball is above the ground in such a way that the cable makes an angle of 25 degrees with the vertical, determine:
Draw a sketch of this situation below
 
 

 What do you have to subtract to find the height?

 Solve for the height

 What kind of energy does it have at this point?

If it suddenly was released, what kind of energy would it have at the bottom?

Solve for the velocity at the bottom
 
 

What is the formula for momentum?

Symbolically, show the conservation of momentum formula below

What would the formula look like if you had an ELASTIC collision between 2 objects
 

What would the formula look like if you had an INELASTIC collision between 2 objects
 

What would the formula look like if you had 1 object that split into 2 objects.
 
 

A 675 kg car traveling at 15 m/s strikes another car at rest. The second car ( 525 kg) moves at what velocity if the 1st car comes to rest?
 
 

What velocity would BOTH cars move had they become connected?
 
 

A loaded cannon with ball has a mass of 250 kg. What is the velocity of a 5 kg ball if the cannon moves backwards at 0.5 m/s?
 
 
 

A 145 kg linebacker moving at 1.5 m/s to the west strikes a 165 Kg runningback who momentarily stops before the collision. The linebacker moves at 32 degrees N of W after the collision and the runningback moves at 66 degrees S of W.

Draw the sketch for this situation below

Due to the angles you must use the what to solve this problem?
 

Write an equation for the X direction
 
 

Write an equation for the Y direction
 
 

Solve simultaneously for the velocity of each player