Engineering Mechanics: Dynamics 12th. Edition by R. C. HIBBELER | 9780136077916 | 0136077919 | Holooly

Mechanics Dynamics

Engineering Mechanics: Dynamics

150 SOLVED PROBLEMS

Question: 12.27

At the instant shown in Fig. 12-45a, cars A and B are traveling with speeds of 18 m/s and 12 m/s, respectively. Also at this instant, A has a decrease in speed of 2 m/s², and B has an increase in speed of 3 m/s². Determine the velocity and acceleration of B with respect to A. ...

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Velocity. The fixed x, y axes are established at a...

Question: 17.13

Determine the angular acceleration of the spool in Fig. 17-20a. The spool has a mass of 8 kg and a radius of gyration of kG = 0.35 m. The cords of negligible mass are wrapped around its inner hub and outer rim. ...

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SOLUTION I Free-Body Diagram. Fig. 17-20b. The 100...

Question: 21.7

The top shown in Fig. 21-20a has a mass of 0.5 kg and is precessing about the vertical axis at a constant angle of θ = 60°. If it spins with an angular velocity ωs = 100 rad/s, determine the precession ωp. Assume that the axial and transverse moments of inertia of the top are 0.45(10^-3) kg · m² ...

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Equation 21-30 will be used for the solution since...

Question: 21.6

The 10-kg flywheel (or thin disk) shown in Fig. 21-14a rotates (spins) about the shaft at a constant angular velocity of ωs = 6 rad/s. At the same time, the shaft rotates (precessing) about the bearing at A with an angular velocity of ωp = 3 rad/s. If A is a thrust bearing and B is a journal ...

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SOLUTION I Free-Body Diagram. Fig. 21-14b. The ori...

Question: 21.5

The airplane shown in Fig. 21-13a is in the process of making a steady horizontal turn at the rate of ωp. During this motion, the propeller is spinning at the rate of ωs. If the propeller has two blades, determine the moments which the propeller shaft exerts on the propeller at the instant the ...

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Free-Body Diagram. Fig. 21-13b. The reactions of t...

Question: 21.4

The gear shown in Fig. 21-12a has a mass of 10 kg and is mounted at an angle of 10° with the rotating shaft having negligible mass. If z Iz = 0.1 kg· m², Ix = Iy = 0.05 kg· m², and the shaft is rotating with a constant angular velocity of ω = 30 rad/s, determine the components of reaction that the ...

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Free-Body Diagram. Fig. 21-12b. The origin of the ...

Question: 21.3

A 5-N · m torque is applied to the vertical shaft CD shown in Fig. 21-10a, which allows the 10-kg gear A to turn freely about CE. Assuming that gear A starts from rest, determine the angular velocity of CD after it has turned two revolutions. Neglect the mass of shaft CD and axle CE and assume that ...

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The principle of work and energy may be used for t...

Question: 21.2

The rod in Fig. 21-9a has a weight per unit length of 1.5 lb/ft. Determine its angular velocity just after the end A falls onto the hook at E. The hook provides a permanent connection for the rod due to the spring-lock mechanism S. Just before striking the hook the rod is falling downward with a ...

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The principle of impulse and momentum will be used...

Question: 21.1

Determine the moment of inertia of the bent rod shown in Fig. 21-5a about the Aa axis. The mass of each of the three segments is given in the figure. ...

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Before applying Eq. 21-5, it is first necessary to...

Question: 21.9

The motion of a football is observed using a slow-motion projector. From the film, the spin of the football is seen to be directed 30° from the horizontal, as shown in Fig. 21-24a. Also, the football is precessing about the vertical axis at a rate Φ = 3 rad/s. If the ratio of the axial to ...

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Since the weight of the football is the only force...

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