the percentage of shots the player makes. We suspect that practice will CAUSE the player's performance to be higher. We call the performance the dependent variable because we expect it depends on how much practice a player gets. To verify or prove false the hypothesis, we manipulate one variable (practice time) to see how it affects the other variable. The one we manipulate is the independent variable, which causes changes in the dependent variable.

PROBLEMS

1. Name the relationship described by each of the following lines or curves.
Graphic relationships can be expressed as equaitons.
2. Write the general form of each relationship depicted in 1.

3. Given the following relationship,

a. write the relationship between F and R; sketch a graph that shows the shape of the curve of a graph of F vs R.
b. write the relationship between F and v; sketch a graph that shows the shape of the curve of a graph of F vs v.
c. write the relationship between m and R; sketch a graph that shows the shape of the curve of a graph of m vs R.

d. In each of (a) to (c ), which variable is the dependent variable?

e. In each of (a) to (c ), which variable is the manipulated?

f. If F is centripetal force on an object traveling in a circle at constant speed, and R is the radius of the circle, write a simple hypothesis consistent with (a) above.

ANSWERS
1.
a. direct proportion
b. linear
c. linear
d. direct proportion
e. inverse
f. power
g. power

2.
a. y = mx

b. y = mx + b

c. y = mx + b

d. y = mx

e. y = 1/(xⁿ)

f. y = mxⁿ

g. x = myⁿ

a. Graph of inverse relationship. b. Graph of a portion of a simple parabola. c. Graph of a simple linear relationship.

d. F, F, R

e. R, v, m

f. For a car turning an unbanked corner, the larger the radius of the curve, the smaller the turning force required.