Concept explainers
(a)
The magnitude and direction of the sled’s acceleration.
(a)
Answer to Problem 43P
The magnitude of the sled’s acceleration is
Explanation of Solution
Write the expression for the Newton’s second law of motion acting on the surface.
Here,
Since the surface is frictionless, the only forces in the plane of the motion are the children’s force.
Using the figure
Here,
Using the figure
Here,
Use equation (II) to solve for
Use equation (III) to solve for
Write the expression for the magnitude of the acceleration.
Here,
Write the expression for the direction of the acceleration.
Conclusion:
Substitute
Substitute
Substitute
Substitute
Below the
Therefore, the magnitude of the sled’s acceleration is
(b)
The time taken by the sled to reach a speed of
(b)
Answer to Problem 43P
The time taken by the sled to reach a speed of
Explanation of Solution
Write the expression for the equation of motion.
Here,
The sled is initial at rest with velocity
Use equation (VIII) to solve for
Conclusion:
Substitute
Therefore, the time taken by the sled to reach a speed of
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Chapter 4 Solutions
COLLEGE PHYSICS,VOL.1
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