Energy
1. Mechanical energy is the total kinetic and ___ energies in a system
potential
10. A bowling ball weighing 1.2 Newtons is lifted 2 meters. How much work is done?
24 joules
work = force x distance
13. A winding mountain road is an example of what simple machine?
inclined plane
25. A system of pulleys is called a(n) ____.
block and tackle
6. Identify the three forms of potential energy.
chemical, gravitational, elastic
17. The efficiency of a machine is always ___ 100 percent.
less than
16. In the equation Win = Wout what does each stand for?
work input and work output
22. A bar that is free to pivot about a fixed point is called a ___
lever
11. Classify the following as having kinetic or potential energy.
Parked car, Rolling stone, Standing giraffe, Swimming dolphin, Rain, Popcorn
Potential: car, giraffe, popcorn
Kinetic: stone, dolphin, rain
8. Energy stored in loaded slingshot is ___ potential energy.
elastic
37. A kid uses 500 Newtons to move a cart of water bottles 30 meters. How much works was done?
15,000 joules
5. A ___ is a unit of measure for all forms of energy.
joule
14. Two or more simple machines that work together are called ___
compound machine
7. You plug in an electric heater to keep you warm. How did energy change form?
electrical changes to thermal
2. Energy that is stored is ___ energy.
potential
18. The amount of work required for a dup truck to move a mound of dirt 10 meters using a force of 70 Newtons is what?
700 joules
4. State the Law of Conservation of Energy
Energy cannot be created or destroyed, just change form
15. Which two simple machines are part of a pair of scissors?
29. An inclined plane wrapped around a cylindrical post is a ____.
screw
12. Define Energy
The ability to cause change
26. A weightlifter bench presses a 1000 N barbell 2 meters in 3 seconds. How much power is used?
2500 J/ 3s = 833 watts * students must calculate work
9. Unit used to measure the amount of energy that people get from food.
calorie
39. A book sitting on a bookshelf has ____ potential energy.
gravitational
34. Describe a least two ways machines make work easier.
increase force, increase distance force is applied, or change direction of the force