DYNAMICS - Lecture Notes / Mehmet Zor

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23 Agust, 2024

Questions with answers

about kinetics of rigid body

4.3

DYNAMICS - Lecture Notes / Mehmet Zor

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23 Agust, 2024

4.3 Kinetics of Rigid Body / Exam questions with answers

DYNAMICS - Lecture Notes / Mehmet Zor

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23 Agust, 2024

4.3 Kinetics of Rigid Body / Exam questions with answers

DYNAMICS - Lecture Notes / Mehmet Zor

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23 Agust, 2024

Question 4.3.3) A rope is passed through pulley B, with a radius of 0.5m and a mass of 30kg, and pulley C, whose weight is neglected. A mass A weighing 10kg is tied to the other end of the rope. An external moment M applied to pulley B causes this pulley to gain an angular acceleration of α = 2 rad/s². In this case, calculate the force in the rope, the external moment M, and the reaction force at joint B.

Answer: T=108.1N, M=61.55 N, R= 361.14 N

4.3 Kinetics of Rigid Body / Exam questions with answers

DYNAMICS - Lecture Notes / Mehmet Zor

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23 Agust, 2024

Question 4.3.4) In the system shown in the figure, when the rod is in the vertical position, it has an angular velocity of ω in the clockwise direction and the spring is of unextended length. What must be the angular velocity of ω for the rod to stop when it reaches the horizontal position?

I_G = ml²/12 , m = 3 kg , k = 200 N/m , Answer: ω = 1.567 rad/sn

4.3 Kinetics of Rigid Body / Exam questions with answers

DYNAMICS - Lecture Notes / Mehmet Zor

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23 Agust, 2024

Question 4.3.5) A thin rod, 600 mm long, has a mass of 10 kg and is attached so that it rotates freely about a vertical axis passing through O. When the rod is in equilibrium, a horizontal force F with an initial value of 150 N is applied to the rod. Calculate the horizontal component of the initial value of the reaction force at O. (Answer: 75N)

4.3 Kinetics of Rigid Body / Exam questions with answers

DYNAMICS - Lecture Notes / Mehmet Zor

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23 Agust, 2024

Question 4.3.6) The system in the figure consists of a 25N rod AC, a 60N disk C attached to it, and a BD spring of unextended length 0.3m. The system is brought to the horizontal position θ = 0^o and in this position, a constant angular velocity of 3 rd/sec is given to the disk C in the counterclockwise direction. The system is released from this horizontal position. Neglecting friction, determine the angular velocity of the AC rod as it passes through the vertical position θ = 90^o. Answer: 5.07 rad/s

4.3 Kinetics of Rigid Body / Exam questions with answers

DYNAMICS - Lecture Notes / Mehmet Zor

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23 Agust, 2024

Question 4.3.7)

The system in the figure consists of pulleys A and B, a rope attached to these pulleys, and a mass C attached to the rope. While the system is at rest, it is released and begins to move. Calculate the speed of mass C when it descends 0.5 m. The mass of the rope and frictions will be neglected, it will be assumed that the rope does not slip and the pulleys are thin discs.

Given: (m_A = 3kg, m_B = 10kg, m_C =2kg. Radii are indicated in the figure.)

Answer: v_C = 1.52m/s

4.3 Kinetics of Rigid Body / Exam questions with answers

DYNAMICS - Lecture Notes / Mehmet Zor

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23 Agust, 2024

Question 4.3.8)

Two equal rods, each 3 meters long and 10 kg mass, are connected at point B by a hinge that allows rotation. While the system is kept motionless at q=60⁰, it is released and starts to move. Calculate the angular velocities of the rods as they pass through position q=90⁰. (Neglect friction.)

Answer: ω = 1.25rad/s

4.3 Kinetics of Rigid Body / Exam questions with answers

DYNAMICS - Lecture Notes / Mehmet Zor

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23 Agust, 2024

Question 4.3.9)(*)

In the system shown in the figure, a block B is hung on the pulley centered at O. While the block is moving down at a speed of 3m/s, the AD hand brake mechanism is activated and the brake pad at C rubs against the pulley with a hand force of P=100N, and the system is stopped after a certain period of time. Since the coefficient of kinetic friction between the pad and the pulley is μ_k=0.5, calculate how far down the block B will go from the moment of braking until the system stops. (m_O = 50kg for the pulley, radius of gyration: k_O = 0.23m, mass of B m_B =15kg) Answer: 9.75m

4.3 Kinetics of Rigid Body / Exam questions with answers