Monday, February 20, 2017



Essay questions and problems

 

1.       Momentum is ____________________________________________________________
2.       Impulse is _______________________________________________________________
3.       Conservation of momentum theorem states that ________________________________
4.       Elastic collision is ____________________________________________________,
Inelastic collision is ____________________________________________________.
9, 18, 20 ,25, 66
5.       Write and explain the formula for rockets ___________________________________________
6.       What are the physical meanings of the symbols on the figure?


7.       What is uniform circular motion? _____________________________________________
8.       What is period and what is frequency?
9.       The formula that relates period and frequency is _____________________________
10.   Tangential speed formula ___________________________________
11.   Angular speed is ____________________________
12.   Formula that relates tangential and angular speed ___________
13.   Centripetal force is ________________________________________
14.   Why centrifugal force is a misconception?
15.   Draw the radius vector, the tangential speed vector and the centripetal acceleration is the motion is counterclockwise.

16.   The universal law of gravitation states that _________________________________
17.   The formula that gives the universal law of gravitation is _________________________________________
18.   Binding energy is _______________________________________________ 
19.   Escape speed is ___________________________________________________
         4. 7. 17. 18. 26. 41. 55.

Saturday, February 4, 2017



                                                     Universal Gravitation                                   Name:

1. The evidence that stimulated Newton to propose the law of universal gravitation emerged from a
study of ____.
a. the motion of the moon and other celestial or heavenly bodies
b. the fall of an apple to the Earth
c. the gravitational interaction of smaller objects upon the Earth
d. ...nonsense! There was no evidence; it was just proposed as a theory.

2. The universal of Newton's law of universal gravitation is a common source of confusion. The
universal means that _____.
a. the amount of gravitational forces is the same for all objects.
b. the acceleration caused by gravity is the same for all objects.
c. the force of gravity acts between all objects - not just between the Earth and an object, but also
between two people. All objects with mass attract.

3. According to Newton's gravitation law, the force of gravitational attraction between a planet and an
object located upon the planet's surface depends upon _____. Choose all that apply.
a. the radius of the planet b. the mass of the planet
c. the mass of the object d. the volume of the object
e. … nonsense! None of these variables affect the force of gravity.

4. The more massive that an object is, the ______ (more, less) that the object will be attracted to Earth.

5. The more massive the Earth is, the ______ (more, less) that another object will be attracted to Earth.

6. The greater that Earth's radius is, the ______ (more, less) that another object will be attracted to
Earth.

7. In the mathematical form of Newton's law of universal
gravitation (see equation at right), the symbol G
stands for _____.
a.     gravity b. the acceleration of gravity c. the gravitational constant

8. TRUE or FALSE:
The value of G (in the equation above) is an enormously large number; that explains
why (at least in part) the force of gravitational attraction between the Sun and the very
distant Earth is such a large number.

9. TRUE or FALSE:
Two lab partners attract each other with a gravitational force. However,
it is impossible to calculate such a force since it is only an unproven
theory.

10. TRUE or FALSE:
The notion that any two objects attract each other gravitationally is a
theory. There is no empirical evidence for such a notion.

11. Orbiting astronauts on the space shuttle do not have weight in space because _____.
a. there is no gravity in space b. there is no air resistance in space
c. there are no scales in space d. the food is terrible and they work all the time
e. ... nonsense! The astronauts do have weight in space.