GuruMCQs.com provides all updated Mechanical Engineering Multiple Choice Questions (MCQs). The most frequently repeated mechanical MCQs section is frequently encountered in FPSC, PPSC, ETEA, NTS, Army, Navy, Air Force, educators, and various other competitive exams, as well as government and private job assessments. Most repeated mechanical engineering MCQs cover topics like Engineering Materials, Fluid Mechanics, Hydraulic Machines, Machine Design, Engineering Mechanics, Nuclear Power Plants, Steam Boilers, Engines, Nozzles, Turbines, Compressors, Gas Turbines, Jet Engines, Thermodynamics, Engineering Metrology, Heat Transfer, etc. Preparing with these MCQs can significantly contribute to your success in government job exams and interviews. Whether you are aiming to establish a career in engineering or seeking to enhance your existing skills, the Mechanical Engineering MCQs at www.gurumcqs.com serve as a valuable resource. Stay committed to regular practice and empower yourself with the knowledge needed to excel in your academic and professional endeavors.
**121. Friction force for dry surfaces. Friction force is________________?**
Pick up wrong statement:
A. proportional to normal load between the surfaces
B. dependent on the materials of contact surface
C. **proportional to velocity of sliding**
D. independent of the area of contact surfaces
E. none of the above is wrong statement
**122. The weight of a body is due to ___________________?**
A. centripetal force of earth
B. **gravitational pull exerted by the earth**
C. forces experienced by body in atmosphere
D. force of attraction experienced by particles
E. gravitational force of attraction towards the center of the earth
**123. When trying to turn a key into a lock, following is applied _____________________?**
A. coplanar force
B. non-coplanar forces
C. lever
D. moment
E. **couple**
**124. According to principle of transmissibility of forces, the effect of a force upon a body is_________________?**
A. maximum when it acts at the center of gravity of a body
B. different at different points in its line of action
C. **the same at every point in its line of action**
D. minimum when it acts at the C.G. of the body
E. none of the above
**125. A number of forces acting at a point will be in equilibrium if_____________________?**
A. their total sum is zero
B. two resolved parts in two directions at right angles are equal
C. **sum of resolved parts in any two perpendicular directions are both zero**
D. all of them are inclined equally
E. none of the above
**126. According to principle of moments__________________?**
A. if a system of coplanar forces is in equilibrium, then their algebraic sum is zero
B. **if a system of coplanar forces is in equilibrium, then the algebraic sum of their moments about any point in their plane is zero**
C. the algebraic sum of the moments of any two forces about any point is equal to moment of their resultant about the same point
D. positive and negative couples can be balanced
E. none of the above
**127. If a rigid body is in equilibrium under the action of three forces, then _____________________?**
A. these forces are equal
B. **the lines of action of these forces meet in a point**
C. the lines of action of these forces are parallel
D. B. and C. above
E. none of the above
**128. A heavy ladder resting on floor and against a vertical wall may not be in equilibrium, if____________________?**
A. the floor is smooth, the wall is rough
B. the floor is rough, the wall is smooth
C. **the floor and wall both are smooth surfaces**
D. the floor and wall both are rough surfaces
E. will be in equilibrium under all conditions
**129. Which of the following is not a vector quantity __________________?**
A. weight
B. velocity
C. acceleration
D. force
E. **moment**
**130. Two non-collinear parallel equal forces acting in opposite direction__________________?**
A. balance each other
B. constitute a moment
C. **constitute a couple**
D. constitute a moment of couple
E. constitute a resultant couple**