[حبوني]

بلييييييييييييييييييييييز سااااااااااااااااااااااعدوني



1. What is friction?

2. How can you reduce friction between 2 surfaces

3. Fk = μkN, What is μk ?

4. Define gravitation

5. State Newton’s law of gravitation?

6. What is G?

7. Distinguish between frictional force and gravitational force

8. Define work

9. State the unit of work

10. Is work a scalar or vector?

11. If there is no displacement, what is the work done.

12. If the normal force is 8 N and the coefficient of static friction is 0.6 , find the static friction?



13. If a force of 10 N acts on a body causing it to move a distance of 10 m in the direction of the force, find the work done by the force.


14. Give some examples of contact forces.





FILL IN THE BLANKS:
1. The force that opposes motion is called ____________
2. The two different types of friction are _______________ and __________________
3. Catching a ball is an example of ___________ force.
4. When an object is moving Fk is _____________ than Fs max.
5. The value of the Gravitational constant G is ________________.
6. _____________- pulls the objects towards one another.
7. If the distance between two objects increases, then the force of gravity _______________
8. Force of gravity depends on mass and_____________________
9. Fk = μkN
Fk = _____________
μk=__________________

N= ___________
10. Friction acts __________ parallel to the surfaces in contact.
11. Friction in fluids is called ____________.
12. _______________ is a force that tries to stop things moving.



MATCH THE FOLLOWING:
Physical quantity
unit
1. Force kilogram
2. Mass kilometer
3. Distance Nm²/kg²
4. Gravitational constant newton