Concept explainers
(a)
Speed of the sled and rider.
(a)
Answer to Problem 77P
Speed is
Explanation of Solution
Write down the equation of energy conservation.
Here
Write the equation for initial and final kinetic energy
Here
Write down the equation for initial and final gravitational potential energy.
Here
Substitute (II) and (III) in (I)
Rearrange (IV) in terms of
Conclusion:
Substitute
Speed is
(b)
Magnitude of force on water
(b)
Answer to Problem 77P
Force is
Explanation of Solution
Write the energy conservation equation for a motion incorporated with frictional force
Here
Substitute (II) and (III) in (VI)
Final kinetic energy is also zero as the final velocity is zero.
Now rearrange (VII) in terms of
Write the equation for normal force acting
Therefore total force on water is,
Here
Conclusion:
Substitute
Substitute
Substitute
Force is
(c)
Force exerted by the chute.
(c)
Answer to Problem 77P
Force is
Explanation of Solution
Use Pythagoras theorem to get the angle of slide
Here
Write the equation for force on
Conclusion:
Substitute
Substitute
Force is
(d)
Force exerted by chute on point C.
(d)
Answer to Problem 77P
The force is
Explanation of Solution
Write the equation for net force.
Here
Write the equation for
Here
Equate (XIII) and (XIV) and write for
Conclusion:
Substitute
The force is
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Chapter 7 Solutions
Bundle: Principles of Physics: A Calculus-Based Text, 5th + WebAssign Printed Access Card for Serway/Jewett's Principles of Physics: A Calculus-Based Text, 5th Edition, Multi-Term
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