Deterning the mangetic energy/ conform the conversion of the energy in magnetic system

Part 1. Determent the relationship between the magnetic force and distance

Set up the equriment as shown.

1.Put one book under one end of the air track. Turn on the air source. Find a position makes equalibrium. Measure the distance between the two magents. Measure the angle between  the track and horizontal.

2. Repeat last step with two books under the track.

3.Adding one book each times until we got 5 groups of data.

4. Measure the mass of the cart.

5.Enter those data to Log Pro.

6.Calculate the force in each position. F=sin(angle)mg

7.Use Log Pro power fit the Force Vs. Distance graph.

F=A*d^B

A=0.002036

B=-1.388

F=0.002036*d^-1.388

Part2. Conform the conversion of energy in this magnetic system.

1.Set a motion sensor on the end of the track.

2.level the air track.

3.Turn on the air track.

4.Record the date while the cart moving toward the magent and the motion it repels by the magnet.

5.Measure the distance between the stationaly magnet and the motion sensor.(L=0.043m)

6.Add a new calculation column named KE (kinetic energy) = 0.5*mass of the cart*"velocity"^2

7.Add a new calculation column named PE （Potential energy）= the intergation of the force by distance=(A/B+1)*(x-L)^(B+1)

8.Add a new calculation column named Total energy=KE+PE

Garph the total energy.

the graph shows the total energy is constant that could conform the conversion of energy threom