Circular Motion Labs

Hypothesis: I can calculate a believable μ for an incline plane ride.

Introduction: Fll is not a real force, but merely the sum of the normal force and weight. Normal force is the force of the object parallel to the surface, and the weight is mass multiplied by gravity on Earth. Using theta, can calculate Fll and Fn (normal force). Also, in the following problem (Ex. 1), notice that the μs is always greater than the μk.

Ex. 1) We can connect Fll and Fn with Newton's second law: ΣF=ma.

m= 10.0 kg θ= 34.0 Ñ" μs=.400 μk=.200

a.) What is Fll?

b.) What is N?

c.) What is Ff for rest?

d.) Does the child move? (Yes, if Fll > Ff)

e.) What is Ff for motion?

f.) What is the acceleration for the sliding child?

Procedure: See lab book.

Data:

Time Distance θ vi a μ

Trial 1 4.0 s 12 m 40Ñ" 0 1.5 m/s2 64 x 10-2 m/s2

Trial 2 4.0 s 12 m 40Ñ" 0 1.5 m/s2 64 x 10-2 m/s2

Trial 3 5.0 s 12 m 40Ñ" 0 96 x 10-2 m/s2 71 x 10-2 m/s2

Sample Calculations:

Conclusion: I successfully calculated the μ on one out of three trials of an incline plane ride.

Analysis: In order to find the distance of the incline, we have to measure the length on the ground. This is done by counting how many feet (actual person's feet) it takes to get from one end of the ride to the other. Then using theta and this measurement, we can substitute the numbers into the trigonometric function cosθ=a/h to find the hypotenuse (the distance). In this process, we lose the accurate significant figures because frankly, our measurement