Applied Dynamics Questions

5/26/2018 Applied Dynamics Questions

1/5

Q. No.(1)- (a)How can you obtain the final momentum of a particle which is moving with a velocity

1V

and acted upon by a force F

during the interval of time (t2-t1)?

(b) Two bodies of 8 kg and 6 kg respectively move with velocities as shown in figure below.

Determine the velocities of each body directly after impact if the coefficient of restitution is 0.6.

Q. No.(2)A double pendulum, as shown in the figure below, oscillates in the XY plane. At the instant

shown 1= 2 rad/sec counter- clockwise and 2= 3 rad/sec counter- clockwise. What is oH

at this

instant if m1=m2= 1 kg? Note that the lower pendulum is connected to mass m1by a pin joint and isfree to rotate about this point.

Q. No. 3 (a)Differentiate between conservative and non-conservative forces with examples.

(b)A 15 kg slender rod AB is 1.5 m long and is pivoted about a point O which is 0.3 m from end B.

The other end is pressed against a spring of constant K= 300 KN/m until the spring is compressed 25

mm. The rod is then in a horizontal position. If the rod is released form this position, determine its

angular velocity as the rod passes through a vertical position.

Q. No. 4 (a)what do you mean by constrained motion in a plane? Also state D Alemberts principle

for the plane motion of a rigid body.

(b)Load B is connected to a double pulley by one of the two inextensible cables as shown in thefigure below. The motion of the pulley is controlled by cable C, which has a constant acceleration of

1.5 m

0.3 m


2/5

22.5 m/sec2and an initial velocity of 300 mm/sec, both directed to the right. Determine number of

revolutions executed by the pulley in 2 seconds and the velocity of load B after 2 seconds.

Q.No.(1)-(a)Deduce the relation for tangential and normal components of acceleration whena particle is moving along a curvilinear path. (4)

(b)The magnitude and direction of the velocities of two identical smooth balls before they

strike each other are as shown in figure below. Assuming coefficient of restitution e=0.80,

determine the magnitude and direction of the velocity of each ball after the impact. How

much kinetic energy will be lost due to the impact?

(6)

Q.No.(2)-(a) Deduce the relationship for principle of work and energy. Illustrate its

application also. (4)

(b)The 2-lb block is given an initial velocity of 20 ft/sec when it is at A. If the spring has an

unstretched length of 2 ft. and a stiffness of K=100 lb/ft, determine the velocity of the block

when S=1 ft. (6)

75 mm

100 mm


3/5

Q.No.(3)(a)What is a general plane motion of a rigid body? Give suitable examples. (3)

(b) A drum of radius 100 mm is mounted on a wheel of radius 150 mm as shown in figure

below, where a rope is wound around the drum. The end E of the rope is pulled with a

constant velocity VE=0.6 m/sec (to the right) and the wheel rolls without slipping. Using

velocity centre, determine: (7)

(i) velocity of point D

(ii) rate at which rope is being wound or unwound

Q.NO.(4)-(a) Obtain the expression for kinetic energy in translation, rotation and general

plane motion of the rigid body. (4)

(b)How do you obtain the angular momentum of a rigid body in plane motion? (6)

OR,

A rectangular plate of mass 20 kg is suspended from pins A and B as shown in figure. If pin

B is suddenly removed, determine:

i) the angular acceleration of the plate,

ii) the components of the reaction at pin A, immediately after pin B has been removed.


4/5

(1) A 10-kg block A is released from rest 2 m above the 5-kg plate P, which can slide freely

along the smooth vertical guides BC and DE. Determine the velocity of the block and plate

just after impact. The coefficient of restitution between the block and the plate is e = 0.75.

Also, find the maximum compression of the spring due to impact. The spring has an

unstretched length of 600 mm.

OR

Disks A and B have a mass of 6 kg and 4 kg, respectively. If they are sliding on the smooth

horizontal plane with the velocities shown, determine their speeds just after impact. The

coefficient of restitution between the disks is e = 0.6

(2) In the engine system shown, the crank AB has a constant clockwise angular velocity of 2000 rpm.For the crank position indicated, determine:

(a) the angular velocity of the connecting rod BD,

(b) the velocity of the piston P.


5/5

(3) A 109 kg block is suspended from an inextensible cable which is wrapped around a drum of 380

mm radius rigidly attached to a flywheel. The drum and flywheel have a combined centroidal

moment of inertia= 1.45 kg-m2. At the instant shown, the velocity of the block is 1.83 m/s directed

downward. Knowing that the bearing at A is poorly lubricated and that the bearing friction is

equivalent to a couple Mof magnitude 81.4 N-m, determine the velocity of the block after it has

moved 1.22 m downward.

OR

A slender 4-kg rod can rotate in a vertical plane about a pivot at B. A spring of constant k = 400 N/m

and of unstretched length 150 mm is attached to the rod as shown in the figure. Knowing that the

rod is released from rest in the position shown, determine its angular velocity after it has rotated

through 90o.

Documents

Applied Dynamics Questions