# Please, dont compromise if you can’t do it.

Lab Report                                                    Name: ____________________

Section: ___________________

## EXPERIMENT: Centripetal Acceleration

DATA TABLE 1: (varying radius)

Constant hanging mass: _______ (kg)

Constant rotating mass (stopper): ___________ (kg)

 Radius (m) Variable Time( s) 10 revs. Time (s) 1 rev. Circumference 2 π r (m) Velocity (m/s) (velocity)^2 (m2/s2} Trial 1 Trial 2 Trial 3 Trial 4

 Theoretical Fc (N) Experimental Fc (N) Trial 1 Trial 2 Trial 3 Trial 4

DATA TABLE 2: (varying hanging mass)

Constant rotating mass (stopper): ___________ (kg)

 Radius (m) Constant Hanging Mass (kg) Time (s) 10 revs Time (s) 1 rev Circumference 2 π r (m) Velocity (m/s) (velocity)^2 (m2/s2} Trial 1 Trial 2 Trial 3 Trial 4

 Theoretical Fc(N) Experimental Fc(N) Trial 1 Trial 2 Trial 3 Trial 4

DATA TABLE 3: (varying rotating mass)

Constant hanging mass: _______kg

 Radius (m) Constant Rotating Mass (kg) Time –sec 10 revs. Time– 1 rev Circumference 2 π  r (m) Velocity (m/s) Trial 1 Trial 2 Trial 3 Trial 4

 Theoretical Fc(N) Experimental Fc(N) Trial 1 Trial 2 Trial 3 Trial 4

Plot the following graphs:

From Data Table 1:

From Data Table 2:

Centripetal force vs. velocity

Centripetal force vs. velocity-squared

From Data Table 3:

Rotating mass vs. velocity

Rotating mass vs. 1/velocity-squared

Questions:

A.    What is the relationship between the radius and the velocity of the rotating object?

B.     What is the relationship between the velocity of the rotating object and the centripetal force exerted on it?

C.     The moon orbits the Earth at a distance of about 3.84 x 108 meters in a path that takes 27.3 days to complete. What is the centripetal acceleration of the moon?

D.    What is the relationship between the mass of a rotating object and its velocity?

E.     How would the shapes of the first two graphs change if the squares of the velocity were used?

F.      When you swing a bucket of water up and down in a vertical circle you can keep the water in the bucket if you keep the velocity high enough. If you let the bucket slow down you get wet. The critical velocity is the slowest velocity necessary to keep the water in the bucket and not on you. What is the critical velocity for you if the formula is velocity = √(rg) where the radius of your arm swing including the bucket is r and g is the acceleration of gravity? Hint: You must measure or estimate the length from your shoulder to the center of the bucket for the radius.