 Engineering Jobs   »   Mechincal Engineering quizs   »   UPPSC Lecturer Recruitment 2021, UPPSC Lecturer...

# UPPSC Lec’21 ME: Daily Practices Quiz. 22-Nov-2021

Quiz: Mechanical Engineering
Exam: UPPSC AE/Lecturer
Topic: Fluid Mechanics

Each question carries 3 marks
Negative marking: 1 mark
Time: 8 Minutes

Q1. Newton’s Law of viscosity states that “Shear stress” is directly proportional to
(a) Velocity
(c) Shear strain
(d) Viscosity

Q2. If σ be the surface tension of the water, ρ be the mass density g be the gravitational accelerations and d be the diameter of the glass tube, then the capillary rise of water in the glass tube h will be
(a) 2σ/ρgd
(b) σ/2ρgd
(c) 4σ/ρgd
(d) 8σ/ρgd

Q3. The pressure difference (in Pa) in a droplet of a fluid of 0.002m diameter with surface tension of 0.01 N/m is
(a) 10
(b) 20
(c) 4 π
(d) 0.0004 π

Q4. A force of 400 N is required to open a process control valve. What is the area of diaphragm needed for a diaphragm actuator to open the valve with a control gauge pressure of 70 kPa?
(a) 0.0095 m^2
(b) 0.0086 m^2
(c) 0.0057 m^2
(d) 0.0048 m^2

Q5. An oil which has kinematic viscosity 0.2 stokes flows through a circular pipe of 1cm radius. The velocity at which the flow will be critical is about
(a) 2.0 m/s
(b) 1.5 m/s
(c) 0.5 m/s
(d) 4.0 m/s
Q6. ‘A fluid is at rest’ it means that
(a) The fluid has zero normal stress and non-zero shear stress.
(b) The fluid has non-zero normal stress and zero shear stress.
(c) The fluid has non-zero normal stress and shear stress.
(d) The fluid has zero-normal stress and zero shear stress.

Solutions

S1. Ans. (b)
Sol. Newton’s Law of viscosity states that shear stress is directly proportional to rate of shear strain or velocity gradient.
τ∝du/dy
τ=μ du/dy
S2. Ans. (c)
Sol. The capillary rise of water in the glass tube h will be
h=4σcosθ/ρgd
But, for water the value of θ is zero.
So,
h=4σcos0/ρgd=4σ/ρgd

S3. Ans. (b)
Sol. ∆P=4σ/d=4×0.01/0.002=20 Pa

S4. Ans. (c)
Sol. Given that Force (F) = 400 N, Gauge Pressure (P) = 70 kPa
Area of diaphragm(A)
A=Force/Pressure=F/P=400/(70×1000)=0.0057 m^2

S5. Ans. (a)
Sol. Critical Reynold number,
Re=2000
Given that radius of circular pipe R=1cm
So, Diameter D=2R=2cm=0.02m
Also given that Kinematic viscosity, ϑ=0.2stokes=0.2×10^(-4) m^2/sec
Re=(V×D)/ϑ
2000=(V×0.02)/(0.2×10^(-4) )
V=2m/sec
S6. Ans. (b)
Sol. A fluid is at rest means that the fluid has non-zero normal stress and zero shear stress.

Sharing is caring!

×

Thank You, Your details have been submitted we will get back to you. Join India's largest learning destination

What You Will get ?

• Job Alerts
• Daily Quizzes
• Subject-Wise Quizzes
• Current Affairs
• Previous year question papers
• Doubt Solving session

OR Join India's largest learning destination

What You Will get ?

• Job Alerts
• Daily Quizzes
• Subject-Wise Quizzes
• Current Affairs
• Previous year question papers
• Doubt Solving session

OR Join India's largest learning destination

What You Will get ?

• Job Alerts
• Daily Quizzes
• Subject-Wise Quizzes
• Current Affairs
• Previous year question papers
• Doubt Solving session

Enter the email address associated with your account, and we'll email you an OTP to verify it's you. Join India's largest learning destination

What You Will get ?

• Job Alerts
• Daily Quizzes
• Subject-Wise Quizzes
• Current Affairs
• Previous year question papers
• Doubt Solving session

Enter OTP

Please enter the OTP sent to
/6

Did not recive OTP?

Resend in 60s Join India's largest learning destination

What You Will get ?

• Job Alerts
• Daily Quizzes
• Subject-Wise Quizzes
• Current Affairs
• Previous year question papers
• Doubt Solving session Join India's largest learning destination

What You Will get ?

• Job Alerts
• Daily Quizzes
• Subject-Wise Quizzes
• Current Affairs
• Previous year question papers
• Doubt Solving session

Almost there

+91 Join India's largest learning destination

What You Will get ?

• Job Alerts
• Daily Quizzes
• Subject-Wise Quizzes
• Current Affairs
• Previous year question papers
• Doubt Solving session

Enter OTP

Please enter the OTP sent to Edit Number

Did not recive OTP?

Resend 60

By skipping this step you will not recieve any free content avalaible on adda247, also you will miss onto notification and job alerts

Are you sure you want to skip this step?

By skipping this step you will not recieve any free content avalaible on adda247, also you will miss onto notification and job alerts

Are you sure you want to skip this step?