Concept explainers
A 5.00-kg particle starts from the origin at time zero. Its velocity as a function of time is given by
where
(a)
The position of particle as a function of time.
Answer to Problem 11.20P
The position of particle as a function of time is
Explanation of Solution
The mass of particle is
The formula to calculate position of particle is,
Substitute
Conclusion:
Therefore, the position of particle as a function of time is
(b)
The motion of the particle qualitatively.
Answer to Problem 11.20P
The particle is moving in the x-y plane turning to move more parallel to the x-axis.
Explanation of Solution
The motion of a particle is described by the change in position vector (either in magnitude or orientation) with time.
The position of the particle is
Conclusion:
Therefore, the particle is moving in the x-y plane turning to move more parallel to the x-axis.
(c)
The acceleration of the particle as a function of time.
Answer to Problem 11.20P
The acceleration of the particle as a function of time is
Explanation of Solution
The formula to calculate acceleration of particle is,
Substitute
Conclusion:
Therefore, the acceleration of the particle as a function of time is
(d)
The net force exerted on the particle as a function of time.
Answer to Problem 11.20P
The net force exerted on the particle as a function of time is
Explanation of Solution
The mass of particle is
The formula to calculate force exerted on the particle is,
Here,
Substitute
Conclusion:
Therefore, the net force exerted on the particle as a function of time is
(e)
The net torque about the origin exerted on the particle as a function of time.
Answer to Problem 11.20P
The net torque about the origin exerted on the particle as a function of time is
Explanation of Solution
The formula to calculate torque exerted on the particle is,
Substitute
Conclusion:
Therefore, the net torque about the origin exerted on the particle as a function of time is
(f)
The angular momentum of the particle as a function of time.
Answer to Problem 11.20P
The angular momentum of the particle as a function of time is
Explanation of Solution
The mass of particle is
The formula to calculate angular momentum of the particle is,
Substitute
Conclusion:
Therefore, the angular momentum of the particle as a function of time is
(g)
The kinetic energy of the particle as a function of time.
Answer to Problem 11.20P
The kinetic energy of the particle as a function of time is
Explanation of Solution
The formula to calculate kinetic energy of the particle is,
Substitute
Conclusion:
Therefore, the kinetic energy of the particle as a function of time is
(h)
The power injected into the system as a function of time.
Answer to Problem 11.20P
The power injected into the system as a function of time is
Explanation of Solution
The mass of particle is
The formula to calculate power of the particle is,
Conclusion:
Therefore, the power of the particle as a function of time is
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Chapter 11 Solutions
EBK PHYSICS FOR SCIENTISTS AND ENGINEER
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