PDP Physics Lab Report 01
PDP Physics Lab Report – 01
NAME: Wang Xueqian
DATE: 2014/06/21
Introduction
In this experiment, we will investigate the relationship between the linear speed of an object and magnitude of centripetal force acting on it. We will use a stopper moving in a circle to create an upward force on the hanging mass; at equilibrium, the upward force on the mass will exactly equal the centripetal force.
Apparatus
Two-hole Stopper
Plastic Tube
Plastic Clip
Electronic balance
Hooked Masses
Stop Watch
String
Procedures
1. Place the stopper on the end of a meter stick so that half the stopper is on the stick.
2. Move the tube such that the end of the tube nearest the stopper is 0.81m away and attach the clip to the string at the other end of the tube.
3. Attach a hooked mass of 50g to the end of the string.
4. Now begin swinging the stopper. Adjust the speed at which you are swinging the stopper until the clip remains about 1cm below the tube.
5. Measure the time it takes for 30 revolutions.
6. Compute linear speed of the stopper according to data collected in step 5.
7. Compute theoretical speed of the stopper according to weight of the hanging mass.
8. Add more masses to the string and repeat Steps 3-7.
Data Collection
Raw data table
Trials
Time for 30 revolutions (±0.001s)
Average Time for 30 revolutions
Mass (g)
Mass of Stopper (±0.1g)
1
11.22
10.96
200
7.7
10.37
11.28
2
13.59
10.46
250
9.95
10.96
3
10.81
10.00
300
9.22
9.96
This data is obviously abnormal. We did not take it into account.
Data Processing
1. Calculate the linear speed of the object:
Trial 1: V= 2πr/T
=2*0.8*π/ (10.96/30)=13.7 s-1
2. Calculate the theoretical speed of the object:
Trial 1: Fc = W= 0.2kg*9.8N kg-1= 1.96N → ac= Fc/m=254. 5m s-2 Vt= √ac*r= 14.3m s-1
3. Calculate the percentage error in magnitude of the speed
Trial 1: % Error= (Vt-V)/V = 4.38%
Trial
Measured Speed (m s-1)
Theoretical Speed (m s-1)
% Error
Centripetal Force (N)
1
13.7
14.3
4.38%
1.96
2
NAME: Wang Xueqian
DATE: 2014/06/21
Introduction
In this experiment, we will investigate the relationship between the linear speed of an object and magnitude of centripetal force acting on it. We will use a stopper moving in a circle to create an upward force on the hanging mass; at equilibrium, the upward force on the mass will exactly equal the centripetal force.
Apparatus
Two-hole Stopper
Plastic Tube
Plastic Clip
Electronic balance
Hooked Masses
Stop Watch
String
Procedures
1. Place the stopper on the end of a meter stick so that half the stopper is on the stick.
2. Move the tube such that the end of the tube nearest the stopper is 0.81m away and attach the clip to the string at the other end of the tube.
3. Attach a hooked mass of 50g to the end of the string.
4. Now begin swinging the stopper. Adjust the speed at which you are swinging the stopper until the clip remains about 1cm below the tube.
5. Measure the time it takes for 30 revolutions.
6. Compute linear speed of the stopper according to data collected in step 5.
7. Compute theoretical speed of the stopper according to weight of the hanging mass.
8. Add more masses to the string and repeat Steps 3-7.
Data Collection
Raw data table
Trials
Time for 30 revolutions (±0.001s)
Average Time for 30 revolutions
Mass (g)
Mass of Stopper (±0.1g)
1
11.22
10.96
200
7.7
10.37
11.28
2
13.59
10.46
250
9.95
10.96
3
10.81
10.00
300
9.22
9.96
This data is obviously abnormal. We did not take it into account.
Data Processing
1. Calculate the linear speed of the object:
Trial 1: V= 2πr/T
=2*0.8*π/ (10.96/30)=13.7 s-1
2. Calculate the theoretical speed of the object:
Trial 1: Fc = W= 0.2kg*9.8N kg-1= 1.96N → ac= Fc/m=254. 5m s-2 Vt= √ac*r= 14.3m s-1
3. Calculate the percentage error in magnitude of the speed
Trial 1: % Error= (Vt-V)/V = 4.38%
Trial
Measured Speed (m s-1)
Theoretical Speed (m s-1)
% Error
Centripetal Force (N)
1
13.7
14.3
4.38%
1.96
2