Concept explainers
Review Question 3.1 How do we determine how many forces to draw on a force diagram?
The way in which one can draw the forces in a force diagram.
Answer to Problem 1RQ
Solution:
The number of forces in the force diagram must be equal to the number of objects it is interacting with.
Explanation of Solution
Introduction:
Force is a vector quantity and it can be contacting as well as noncontacting in nature.
Explanation:
Consider a ball
Considering ball as the system, there are two forces acting on it, as follows:
The string will apply an upward force of contacting nature:
The earth will apply a downward force of noncontacting nature:
The force diagram for the system of forces is as shown below:
Here, the length of the arrows indicates the magnitude of the forces, and the direction indicates the direction in which they are acting.
Conclusion:
Hence, to determine the number of forces acting on a system, consider only the number of forces acting on it from the objects it is interacting with.
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Chapter 3 Solutions
College Physics
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