Concept explainers
(a)
The constant friction force for the last
(a)
Answer to Problem 25AP
The constant friction force for the last
Explanation of Solution
The mass of the empty car is
Write the formula to calculate the energy by equation of motion
Here,
The formula of initial kinetic energy is,
Substitute
The formula of kinetic energy at final point
Substitute
The formula of the potential energy at start
Substitute
The formula of the potential energy at final point
Substitute
The formula of the energy wasted due to friction
Substitute
Substitute
Conclusion:
Substitute
Therefore, the constant friction force for the last
(b)
The highest speed reached by the car.
(b)
Answer to Problem 25AP
The highest speed reached by the car is
Explanation of Solution
The formula of kinetic energy at final point
The body is at the lowest point so the resistive force is taken upto that point only.
The formula of the energy wasted due to friction
Substitute
Write the formula to calculate the final velocity from equation (1) can be written as,
Conclusion:
Substitute
Therefore, the highest speed reached by the car is
(c)
The new values of friction force and highest speed when the weight is
(c)
Answer to Problem 25AP
The new value of friction force is
Explanation of Solution
The mass of the empty car is
The Write the formula to calculate the
Substitute
To calculate the final velocity the equation (2)
Substitute
Conclusion:
Therefore, the new value of friction force is
(d)
The depth of the underground part of the ride.
(d)
Answer to Problem 25AP
The depth of the underground part of the ride is
Explanation of Solution
Consider
The formula of the potential energy at start
Substitute
The Write the formula to calculate the depth
Conclusion:
Substitute
Therefore, the depth of the underground part of the ride is
(e)
The depth of the underground provided is feasible or not.
(e)
Answer to Problem 25AP
No, the depth of the underground provided is not feasible.
Explanation of Solution
No the depth of the underground tunnel provided is not feasible as the total length covered by the car is increased due to which the loss of energy due to friction is increased a lot as compared to the case when the underground path was not there. The non-conventional forces on the car are increased due to the depth provided as the friction in the path of later
Conclusion:
Therefore, the depth of the underground provided is not feasible.
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Chapter 8 Solutions
PHYSICS:F/SCI.+ENGRS.(LL)-W/SINGLE CARD
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- Physics for Scientists and Engineers: Foundations...PhysicsISBN:9781133939146Author:Katz, Debora M.Publisher:Cengage Learning