Mechanical Engineering Exam > Mechanical Engineering Questions > Fig. shows a quick return motion mechanism in...
Start Learning for Free
Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]?
Most Upvoted Answer
Fig. shows a quick return motion mechanism in which the driving crank ...
Solution:
Given data:
Rotational speed of driving crank OA = 120 rpm
Direction of rotation of driving crank OA = Clockwise
Position of the mechanism is shown in the figure.
To determine:
1. Magnitude and direction of the acceleration of block D
2. Angular acceleration of the slotted bar QB
Acceleration analysis:
Velocity analysis:
The velocity diagram for the quick return mechanism is shown below.
From the velocity diagram,
Velocity of the block D, vD = OB
Velocity of the slotted bar QB, vB = BQ
Velocity of the link AB, vA = OA
Acceleration of the block D:
The acceleration diagram for the quick return mechanism is shown below.
From the acceleration diagram,
Acceleration of the block D, aD = AB + BD
Direction of acceleration of the block D is perpendicular to the direction of vD and towards O.
Magnitude of acceleration of the block D:
vD = OB = 100 mm
Length of link AB, AB = 200 mm
Length of link BD, BD = 300 mm
vA = OA = rω
where, r is the length of the crank OA
ω is the angular velocity of the crank OA in rad/s
Given, Rotational speed of driving crank OA = 120 rpm
∴ ω = 2πN/60 = 2π×120/60 = 4π rad/s
vA = OA = rω = 50×4π = 200π mm/s
Acceleration of the block D, aD = AB + BD
= 200π2/100 + 300(π2/100 + 1)
= 400π2/100 + 300(π2/100 + 1)
= 4π2 + 3π2 + 900
= 7π2 + 900
= 7(3.142)2 + 900
= 7×9.87 + 900
= 69.09 + 900
= 969.09 mm/s2
Direction of acceleration of the block D is perpendicular to the direction of vD and towards O.
∴ Magnitude and direction of the acceleration of block D are 969.09 mm/s2 and towards O respectively.
Angular acceleration of the slotted bar QB:
Angular velocity of the slotted bar QB, ωB = BQ/LB
where, LB is the length of the slotted bar QB
From the velocity diagram,
vB = BQ = 200 mm/s
vB = ωB×LB
ωB = vB/LB
= 200/LB
Differentiating the above equation w.r.t. time,
αB = dωB/dt
= d/dt(200/LB)
= 0 (as LB is constant)
∴ Angular acceleration of the slotted bar QB is zero.
∴ Magnitude and direction of the angular acceleration of the slotted bar QB are zero.
Given data:
Rotational speed of driving crank OA = 120 rpm
Direction of rotation of driving crank OA = Clockwise
Position of the mechanism is shown in the figure.
To determine:
1. Magnitude and direction of the acceleration of block D
2. Angular acceleration of the slotted bar QB
Acceleration analysis:
Velocity analysis:
The velocity diagram for the quick return mechanism is shown below.
From the velocity diagram,
Velocity of the block D, vD = OB
Velocity of the slotted bar QB, vB = BQ
Velocity of the link AB, vA = OA
Acceleration of the block D:
The acceleration diagram for the quick return mechanism is shown below.
From the acceleration diagram,
Acceleration of the block D, aD = AB + BD
Direction of acceleration of the block D is perpendicular to the direction of vD and towards O.
Magnitude of acceleration of the block D:
vD = OB = 100 mm
Length of link AB, AB = 200 mm
Length of link BD, BD = 300 mm
vA = OA = rω
where, r is the length of the crank OA
ω is the angular velocity of the crank OA in rad/s
Given, Rotational speed of driving crank OA = 120 rpm
∴ ω = 2πN/60 = 2π×120/60 = 4π rad/s
vA = OA = rω = 50×4π = 200π mm/s
Acceleration of the block D, aD = AB + BD
= 200π2/100 + 300(π2/100 + 1)
= 400π2/100 + 300(π2/100 + 1)
= 4π2 + 3π2 + 900
= 7π2 + 900
= 7(3.142)2 + 900
= 7×9.87 + 900
= 69.09 + 900
= 969.09 mm/s2
Direction of acceleration of the block D is perpendicular to the direction of vD and towards O.
∴ Magnitude and direction of the acceleration of block D are 969.09 mm/s2 and towards O respectively.
Angular acceleration of the slotted bar QB:
Angular velocity of the slotted bar QB, ωB = BQ/LB
where, LB is the length of the slotted bar QB
From the velocity diagram,
vB = BQ = 200 mm/s
vB = ωB×LB
ωB = vB/LB
= 200/LB
Differentiating the above equation w.r.t. time,
αB = dωB/dt
= d/dt(200/LB)
= 0 (as LB is constant)
∴ Angular acceleration of the slotted bar QB is zero.
∴ Magnitude and direction of the angular acceleration of the slotted bar QB are zero.
Attention Mechanical Engineering Students!
To make sure you are not studying endlessly, EduRev has designed Mechanical Engineering study material, with Structured Courses, Videos, & Test Series. Plus get personalized analysis, doubt solving and improvement plans to achieve a great score in Mechanical Engineering.
|
Explore Courses for Mechanical Engineering exam
|
|
Similar Mechanical Engineering Doubts
Top Courses for Mechanical EngineeringView all
Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]?
Question Description
Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]? for Mechanical Engineering 2024 is part of Mechanical Engineering preparation. The Question and answers have been prepared according to the Mechanical Engineering exam syllabus. Information about Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]? covers all topics & solutions for Mechanical Engineering 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]?.
Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]? for Mechanical Engineering 2024 is part of Mechanical Engineering preparation. The Question and answers have been prepared according to the Mechanical Engineering exam syllabus. Information about Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]? covers all topics & solutions for Mechanical Engineering 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]?.
Solutions for Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]? in English & in Hindi are available as part of our courses for Mechanical Engineering.
Download more important topics, notes, lectures and mock test series for Mechanical Engineering Exam by signing up for free.
Here you can find the meaning of Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]? defined & explained in the simplest way possible. Besides giving the explanation of
Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]?, a detailed solution for Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]? has been provided alongside types of Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]? theory, EduRev gives you an
ample number of questions to practice Fig. shows a quick return motion mechanism in which the driving crank OA rotates at 120r.p.m. in a clockwise direction. For the position shown, determine the magnitude and direction of 1, the acceleration of the block D ; and 2. the angular acceleration of the slotted bar QB. [Ans. 7.7 m/s2 ; 17 rad/s2]? tests, examples and also practice Mechanical Engineering tests.
|
|
Explore Courses for Mechanical Engineering exam
|
|
Suggested Free Tests
Signup for Free!
Signup to see your scores go up within 7 days! Learn & Practice with 1000+ FREE Notes, Videos & Tests.
|
© EduRev
|
Education Revolution
|
Follow Us
|
Signup to see your scores
go up within 7 days!
Access 1000+ FREE Docs, Videos and Tests
Takes less than 10 seconds to signup