Answer:
Friction force is independent of the direction of the contacting surfaces
Explanation:
It can go any way depending on how much force is being out on it.
1. turn off lights in classrooms when not in use.
2. turn off all computers when not in use.
3.use a small amount of water when washing your hands.
4. Don't charge your cell phones during class.
5. open windows instead of using air conditioner
One
If you use the right hand rule for these problems, you usually make your fingers and thumb sit at right angles to each other. What each of the two fingers means and that related to the thumb is a different story. All you have to understand at this point is that all three are mutually perpendicular.
That makes C the answer.
All the other choices don't make that clear.
Two
This is a straight definition question. The definition says exactly what D says.
Answer:
A mousetrap makes use of a simple machine called a lever.
Explanation:
In a second-class lever the effort force is at the other end, with the load in the middle. In a third-class lever, the load is at the end and the effort force is between the fulcrum and the load. When you set the mousetrap, you are using a second-class lever. Sorry if I get this wrong. I am in 5th grade! ♥