Physics Web Search: Torque s3

Determination of the Force of Gravity Go to http://tinyurl.com/ma8rw9x

Qualitative Observations 1. How does the changing the separation (the distance) of the objects affect the force between them? (increases, decreases, not affected)

2. What happens to the force between the objects when mass 1 increases? (increases, decreases, not affected)

3. What happens to the force between the objects if Mass 2 decreases? (increases, decreases, not affected)

4. Compare the force on the blue object to the force on the red object? What if the mass of the blue one is twice as big as the red object? Explain.

5. What direction are the gravitational forces acting on the objects?

Quantitative

It is now time to build a mathematical model.

1. If Force were the dependent variable, what THREE things could be the independent variable?

2. Change the mass of one of the objects and leave all other variables the same. What happens to the force when you… double the mass? triple the mass? quadruple the mass? 3. Does it matter which mass you choose to change to answer question #2?

4. Change the distance of the two objects and leave all other variables the same. When we talk distances here the frame of reference is from the center of one mass to the center of the other mass, not surface to surface. What happens to the force when you… double the distance? triple the distance? (if you have room) quadruple the distance? Questions 1. Explain why varying the second mass had the same effect on the force as varying the first mass.

2. What is the relationship (proportionality) between Mass and force?

3. What is the relationship between distance and the force of gravity?

4. Combine your proportions between Mass 1 (m1), Mass 2 (m2) distance (r) into a single proportion

to the Force of gravity (Fg).

Check with your instructor to make sure your proportionality is correct.

5. Does your lab data for m1, m2, and d equal Fg? Work out your units, do they equal a unit of force?

6. Determine the gravitational constant (G) that will satisfy your units.

G=______

7. Write your full formula and check with your instructor.