Module 3—Effects of Force on Velocity
Lesson Summary
As you worked through this lesson, you should have developed answers to this question:
- How do free-body diagrams, vector analyses, and Newton’s second law help solve moving-object problems?
According to Newton's second law, if an unbalanced force is applied to an object, it will accelerate in the direction of the unbalanced force. The unbalanced force can be a net force, which is the vector sum of all the forces acting on an object. Using the net force, the magnitude and direction of the acceleration can be determined in a variety of situations.
For one- and two-dimensional forces acting on a single body:
- Draw a free-body diagram.
- Using components (if necessary), determine the total net force acting along each axis.
- Draw a vector diagram using the total force acting along each axis.
- Add the total force of each axis as vectors.
- State the net force and acceleration.
For connected bodies:
- Define the directions using a coordinate axes.
- Construct a free-body diagram for each body.
- Generate an equation for the net force and acceleration of each body.
- Combine the equations, and manipulate to solve for the acceleration and/or tension in the system.