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Activity 4.2.2 Newton’s Laws of Motion
Introduction
Aerospace design engineers use aerodynamics, the science of motion of air and
forces acting on bodies in air, to design airplanes that will fly. One of the jobs of an
aerospace engineer is to create wing shapes that produce lift as the air moves over
the wings. If an airplane is going to fly, the amount of lift must be greater than the
force of gravity, and the amount of thrust produced by the engine must be greater
than the drag force created by air resistance. Wing shapes that provide lift and have
the proper angle of attack (the angle at which a wing meets the flow of air) can then
help an airplane overcome gravity. Research has shown that a wing with a
streamlined shape can overcome drag with the thrust of engines. The less drag on
an airplane, the less power it needs to move.
In this activity you will learn the basic concepts of aerodynamics, including basic
definitions, Newton’s laws of motion, and forces acting on an airplane during flight,
and in the next activity, Bernoulli’s principle, which is the major contributor to lift.
Knowledge of these science concepts will help you as you investigate atmospheric
flight and space flight later in this unit.
Equipment
Procedure
Answer the questions below as your teacher guides you through several activities.
Discovery of Forces – Newton’s First Law
Watch your teacher’s demonstration to answer the questions below.
1. Describe Newton’s first law of motion. What would you use for an experiment to
show this?
2. Read the statement below and explain why you agree or disagree with the
statement. Give an example.
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GTT – Unit 4 – Lesson 2 – Activity 4.2.2 – Newton’s Laws of Motion – Page 1
An object at rest will remain at rest unless acted on by an unbalanced force. An
object in motion continues in motion with the same speed and in the same direction
unless acted upon by an unbalanced force.
Changes in Force – Newton’s Second Law
Think about riding a skateboard. If you push off lightly, will you travel very far? What
if you push off harder? When you push off, you are applying a force to an object with
mass (that would be you), and when you put yourself into motion, you are
accelerating.
3. Describe what happens using his law:
4. Write down Newton’s 3rd Law of Motion:
5. Describe an experiment that would demonstrate this law:
6. What does the formula F=ma mean?
Conclusion Questions
Conclusions (answer these questions in COMPLETE sentences)
1. If the mass remains constant and the force changes, what happens to the
acceleration?
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GTT – Unit 4 – Lesson 2 – Activity 4.2.2 – Newton’s Laws of Motion – Page 2
2. If the force remains constant and the mass changes, what happens to the
acceleration?
3. Newton’s second law says that force and acceleration are directly proportional,
meaning that if the force is increased three times, the acceleration should
increase three times. Would this occur in your experiment? If not, why not?
4. What effect does resistance have on the acceleration? Be sure to discuss both
air and friction.
5. Read the statement below and explain why you agree or disagree with the
statement. Give an example.
Acceleration is produced when a force acts on a mass. The greater the mass of the
object being accelerated, the greater the amount of force needed to accelerate the
object. Therefore, Force = mass x acceleration or F = ma.
Project Lead The Way, Inc.
Copyright 2010
GTT – Unit 4 – Lesson 2 – Activity 4.2.2 – Newton’s Laws of Motion – Page 3