Concept explainers
(a)
The reading on the scale in an elevator when elevator accelerates at
Answer to Problem 87QAP
The reading on the scale is
Explanation of Solution
Givendata:
Formula Used:
Newton's second law:
Calculation:
We are interested in calculating the reading on the scale for accelerationof the elevator, at
together as one object.
The reading on the scale is equal in magnitude to the normalforce acting on the dog. Gravity also acts on the dog.
We can use Newton's second law tocalculate N as a function of the acceleration.
We'll define up to be positive y throughout ourcalculation.
Free-body diagram of the dog:
Conclusion:
Thus, we have the reading on the scale in an elevator when elevator accelerates at
(b)
The reading on the scale in an elevator when elevator cruises down at a steady speed.
Answer to Problem 87QAP
The reading on the scale is
Explanation of Solution
Given data:
Formula Used:
Newton's second law:
Calculation:
We are interested in calculating the reading on the scale for elevator cruises down at a steady speed., which is equal to the acceleration of the scale and dog since they traveltogether as one object.
The reading on the scale is equal in magnitude to the normal force acting on the dog. Gravity also acts on the dog.
We can use Newton's second law to calculate N as a function of the acceleration.
We'll define up to be positive y throughout our calculation.
Free-body diagram of the dog:
Conclusion:
Thus, we have the reading on the scale in an elevator
(c)
The reading on the scale in an elevator when elevator accelerates at
Answer to Problem 87QAP
The reading on the scale is
Explanation of Solution
Given data:
Formula Used:
Newton's second law:
Calculation:
We are interested in calculating the reading on the scale for acceleration as
of the elevator, which are equal to the accelerations of the scale and dog since they travel
together as one object.
The reading on the scale is equal in magnitude to the normal force acting on the dog. Gravity also acts on the dog.
We can use Newton's second law to calculate N as a function of the acceleration.
We'll define up to be positive y throughout our calculation.
Free-body diagram of the dog:
Conclusion:
The reading on the scale in an elevator when elevator accelerates at
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