(a)
The force exerted by the chin-up bar on the person’s body at
(a)
Answer to Problem 41P
The force exerted by the chin-up bar on the person’s body at
Explanation of Solution
The slope of the speed versus time graph gives the magnitude of the acceleration. Consider positive slope of speed versus time graph as positive acceleration and negative slope of speed versus time graph gives negative acceleration. When the slope is zero the acceleration is zero.
According to Newton’s second law,
Here,
Rewrite the above equation in terms of
Write the expression to calculate the acceleration.
Here,
From the graph the slope at time
Conclusion:
Substitute
Substitute
Therefore, the force exerted by the chin-up bar on the person’s body at
(b)
The force exerted by the chin-up bar on the person’s body at
(b)
Answer to Problem 41P
The force exerted by the chin-up bar on the person’s body at
Explanation of Solution
The slope of the speed versus time graph gives the magnitude of the acceleration. The slope of the graph at 0.5 s is same as that of 0 s. That is the graph is a straight line at these moment. If the graph is a straight line, the acceleration is same.
The mass of the person does not change and the acceleration is same as that at
Conclusion:
Therefore, the force exerted by the chin-up bar on the person’s body at
(c)
The force exerted by the chin-up bar on the person’s body at
(c)
Answer to Problem 41P
The force exerted by the chin-up bar on the person’s body at
Explanation of Solution
The graph below is the speed versus time graph
From the graph it is evident that at
Conclusion:
Substitute
Therefore, the force exerted by the chin-up bar on the person’s body at
(d)
The force exerted by the chin-up bar on the person’s body at
(d)
Answer to Problem 41P
The force exerted by the chin-up bar on the person’s body at
Explanation of Solution
The graph below is the speed versus time graph.
From the graph the slope at time
Conclusion:
Substitute
Substitute
Therefore, the force exerted by the chin-up bar on the person’s body at
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Chapter 5 Solutions
Physics: for Science.. With Modern. -Update (Looseleaf)
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