Purpose
Investigate Newton's second law of motion.
Concept
Newton's second law of motion states that acceleration is directly proportional to
force and inversely proportional to mass. In this experiment, a dynamic cart will
be accelerated by applying a pulling force with a spring scale.
Materials
meter stick; stopwatch; dynamic cart; masking tape; set of 100 g masses; balance
Procedure Part A - Force and Acceleration
1. Use a balance to find the mass of the cart, and record below.
2. Measure and mark a 40.0 cm distance on the table.
3. Horizontally pull the empty cart with a constant 1.0 N of force and record the time to travel the 40.0 cm interval.
4. Repeat with 2.0 N, 3.0 N and 4.0 N. Record your data in table A.
Part B - Mass and Acceleration
1. Repeat the experiment keeping the force constant at 2.0 N, and changing the mass by 200 g for each trial.
2. For the first trial the cart should be empty. Add 200 g for each trial until you have 600 g in the cart. Record your data in table B.
Observations and Data: Part A - Force and Acceleration
Mass of cart (kg)
Force (N)
Distance (m)
Time (s)
Acceleration (m/s^2)
1.0
.40
2.0
.40
3.0
.40
4.0
.40
Part B - Mass and Acceleration
Mass of cart (kg)
Force (N)
Distance (m)
Time (s)
Acceleration (m/s^2)
2.0
.40
2.0
.40
2.0
.40
2.0
.40
Analysis
Make a graph of Force (horizontal axis) versus acceleration (vertical axis) for part A below.
Make a graph of mass (horizontal axis) versus acceleration (vertical axis) for part B below.
1. Based on your results from this experiment, what is the mathematical relationship between force and acceleration?
2. What is the mathematical relationship between mass and acceleration?
Application
1. Given all other factors staying the same, what would happen to the take-off acceleration of a jet airplane if the plane was carrying an extra heavy load? Explain.
2. Given all other factors staying the same, what would happen to the acceleration of a jet airplane if the thrust force was reduced for take-off? Explain.