Concept explainers
A 300-g mass hangs at the end of a string. A second string hangs from the bottom of
that mass and supports a 900-g mass. (a) Find the tension in each string when the
masses are accelerating upward at
tension in each string when the acceleration is
(a)
The tension in eachstring when the masses are accelerating in upward direction at
Answer to Problem 64SP
Solution:
Explanation of Solution
Given data:
The mass of the block that is hanging on the first string is
The mass of the block that is hanging on the second string is
Upward acceleration of the masses is
Formula used:
From the Newton’s second law of the motion, the expression of the force is
Here,
Explanation:
Draw the free body diagram of the system by analyzing the problem:
In the above diagram,
Draw the free body diagram of the masses separately when acceleration is in upward direction:
Consider free body diagram of the
Consider the direction of the upward forces as positive and the direction of the downward forces as negative. Therefore,
Here,
Substitute
Solve the above equation for
Consider free body diagram of the
Consider the direction of the upward forces is positive and the direction of the downward forces is negative. Therefore,
Substitute
Solve the above equation for
Conclusion:
Therefore, the value of the tension in the strings by which
(b)
The tension in each string when the masses are accelerating in the downward direction at
Answer to Problem 64SP
Solution:
Explanation of Solution
Given data:
The mass of the block that is hanging on the first string is
The mass of the block that is hangingon the second string is
Downward acceleration of the masses is
Formula used:
From the Newton’s second law of the motion, the expression of the force is
Here,
Explanation:
Draw the free body diagram of the each masses separately when acceleration is in downward direction:
Consider the free body diagram of the
Consider the direction of the upward forces as positive and the direction of the downward forces as negative. Therefore,
Substitute
Solve the above equation for
Consider the free body diagram of the
Consider the direction of the upward forces is positive and the direction of the downward forces is negative. Therefore,
Substitute
Solve the above equation for
Conclusion:
Therefore, the value of the tension in the strings by which the
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Chapter 3 Solutions
Schaum's Outline of College Physics, Twelfth Edition (Schaum's Outlines)
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