Newton’s Second Law

UB ForumCategory: PhysicsNewton’s Second Law
Anna Cave Staff asked 3 years ago

Can someone check this Lab for me?

 

Physics Lab 2

Newton’s Second Law

The purpose of this experiment is to validate Newton’s Second Law of Motion. In part A the lab cart will be accelerated by various net forces while keeping mass constant.  In part B the lab cart will be accelerated by a constant net force while its mass is varied.  The goal is to determine the relation between acceleration and force and the relation between acceleration and mass.  The force on the lab cart is controlled and provided by gravity acting on a weight at the end of a string that passes over a pulley at the end of a lab table.

Instructions:

Part A

  • Set M = 99 g and m = 1 g
  • Click the START button.
  • Record the acceleration value.
  • Click the reset button.
  • Repeat the experiment and fill the table below. Force data is collected by calculating the weight of the calibrated masses added to the end of the string. (g= 9.81 m/s²)

 

 

M (g) m (g) a (m/s²) F=mg (N)
99.0 1.0 0.0981 9.810
98.0 2.0 0.1962 19.62
97.0 3.0 0.2943 29.43
96.0 4.0 0.3924 39.24
95.0 5.0 0.4905 49.05
94.0 6.0 0.5886 58.86
93.0 7.0 0.6867 68.67
92.0 8.0 0.7848 78.48
91.0 9.0 0.8829 88.29
90.0 10.0 0.9810 98.10

In this part of the experiment mass is removed from the cart and placed on the end of a string passing over a pulley.  By doing this the amount of net force will be varied while keeping constant the total amount of mass (100 g) being accelerated.  It is important to note that the pull of gravity on the dangling mass causes not only the cart and its contents to accelerate, but also the string itself and the mass or masses attached to the end of the string.  Put another way, the weight on the end of the string causes all of the mass to accelerate (and it all accelerates at the same rate).

Use these results to construct a force vs. acceleration graph.  For this graph, plot the independent variable (force) on the y-axis. Determine the best fit. How does the shape of this graph look? What does this imply about the relationship between force and acceleration when the mass is constant?

 

 

I plot above graph that is a straight line graph and showing direct relation of force and acceleration.

 

Part B

 

  • Set M = 100 g and m = 10 g
  • Click the START button.
  • Record the acceleration value.
  • Click the reset button.
  • Repeat the experiment and fill the table below.

 

M (g) m (g) a (m/s²) M + m (g) F=mg (N) 1/M + m (1/g)
100.0 10.0 0.8918 110 98.1 0.0090
110.0 10.0 0.8175 120 98.1 0.0083
120.0 10.0 0.7546 130 98.1 0.0077
130.0 10.0 0.7007 140 98.1 0.0071
140.0 10.0 0.6540 150 98.1 0.0066
150.0 10.0 0.6131 160 98.1 0.0062
160.0 10.0 0.5771 170 98.1 0.0059
170.0 10.0 0.5450 180 98.1 0.0055
180.0 10.0 0.5163 190 98.1 0.0052
190.0 10.0 0.4905 200 98.1 0.0050