1. Monday PS

2. Conversions
Divide your gram (g) mass value by 1000 to determine the kilogram (kg) value
Divide your speed in (km/hr) by 3.6 to get the speed in (m/s)
(kJ) means kilojoules. Multiply the number of (kJ) by 1000 to get the value of energy in (j)

3. Calculations for the roller coaster Project paper
This is due Wednesday (Tomorrow)
Neat, typed if possible

5. Equations GPE = m g h KE = ½mv2 a = (Vf – Vi)/t p = m v MA = fo / fi
W = f d
P = W / t
Fnet = m a

6. Question #15 Calculate the GPE at start
What is the mass of your marble?
small metal = 28.3 g clear glass = 8.5 g
swirled glass = 6.0 g big metal = 67 g
wood = 2.0 g
What is acceleration due to gravity on Earth?
What is the height?

7. Question #16
Calculate the GPE at the bottom of the first hill

8. Question #17
What is the difference in the amount of GPE in the problems 15 and 16?

9. Question #18
If the all of the ball’s energy lost from GPE was converted into KE at the bottom of the first hill, what is the velocity of the ball?

10. Question #19
What is the acceleration of the ball from the start to the bottom of the first hill, if it takes 5 seconds to travel between points
Initial velocity ?
Final velocity ?

11. Question #20
What is the momentum of the ball at the bottom of the first hill?

12. Question #21
What is the change in GPE of the ball from the start to finish of the roller coaster ride?

13. Question #22
How much energy of the ball was lost due to friction and sound by the end of the roller coaster?
What else could take away some of the ball’s energy?

14. The rest of this week we will concentrate on the equations
Steps to solving a problem using an equation
1) Identify what is given
2) Identify what is wanted
3) Make sure all values are in correct units (kg, m, s , N, J, W)
4) Identify equation that relates the givens to what is wanted
5) Plug in givens
6) Solve for what you want

15. Question
A high jumper jumps 2.04 m. If the jumper has a mass of 67 kg, what is his gravitational potential energy at the highest point of the jump?

16. Plug in and solve GPE = m g h GPE = (67) (10) (2.04) Around 1300 J
The units are the units for energy, which can be used if all else is measured in m, kg, and s

17. Question #2
A rock is rolling down a hill with a velocity of 4.67 m/s. It has the kinetic energy of 18.9 kJ. What is the mass of the rock?

18. Question
A team of horses is hitched to a cart. The team pulls with a force of 471 N. The cart travels 2.3 km in 20 minutes. Calculate the work done on the cart and the power delivered by the horses.

19. Horse problem

20. Make up a problem Person On top of _______ Person’s mass ______
Amount of GPE person has ______
Find height

22. Solution

23. Scientific Notation
A method used to write very large or very small numbers in a more manageable way.
15000 = 1.5 x 104

24. Write in scientific notation
The planet of Saturn has a mass of kg
In 1997, planes either took off or landed at Chicago’s O’Hare airport

25. Complete the questions on the handout in class
Identify
Check units
Find the right Equation
Plug in and solve

26. Homework Pg 858-859 Problems 111-113, 116-125
Due Wednesday in addition to the calculation page of the roller coaster project