300 Important Engineering Mechanics MCQ Question and Answer | PDF Free Download
1.The centre of gravity of a right circular solid cone is at a distance of _________ from its base, measured along the vertical axis.(where h = Height of a right circular solid cone.)
- Ah/2
- Bh/3
- Ch/4
- Dh/6
2.The centre of percussion is below the centre of gravity of the body and is at a distance equal to
- Ah/kG
- Bh2/kG
- CkG2/h
- Dh × kG
3.Moment of inertia of a triangular section of base (b) and height (h) about an axis through its base, is
- ABh3/4
- BBh3/8
- CBh3/12
- DBh3/36
4.The periodic time (T) is given by (where, ω = Angular velocity of particle in rad/s.)
- Aω/2π
- B2π/ω
- C2π × ω
- Dπ/ω
5.Moment of inertia of a triangular section of base (b) and height (h) about an axis passing through its vertex and parallel to the base, is __________ than that passing through its C.G. and parallel to the base.
- ANine times
- BSix times
- CFour times
- DTwo times
6.Which of the following do not have identical dimensions?
- AMomentum and impulse
- BTorque and energy
- CTorque and work
- DMoment of a force and angular momentum
7.Coplanar non-concurrent forces are those forces which __________ at one point, but their lines of action lie on the same plane.
- AMeet
- BDo not meet
- CEither ‘A’ or ‘B’
- DNone of these
8.A trolley wire weighs 1.2 kg per meter length. The ends of the wire are attached to two poles 20 meters apart. If the horizontal tension is 1500 kg find the dip in the middle of the span
- A2.5 cm
- B3.0 cm
- C4.0 cm
- D5. 0 cm
9.In determining stresses in frames by methods of sections, the frame is divided into two parts by an imaginary section drawn in such a way as not to cut more than
- ATwo members with unknown forces of the frame
- BThree members with unknown forces of the frame
- CFour members with unknown forces of the frame
- DThree members with known forces of the frame
10.In ideal machines
- AMechanical advantage is greater than velocity ratio
- BMechanical advantage is equal to velocity ratio
- CMechanical advantage is less than velocity ratio
- DMechanical advantage is unity
11.The Forces are called coplanar when all of them acting on body lie in
- AOne point
- BOne plane
- CDifferent planes
- DPerpendicular planes
12.The moment of inertia of a solid cylinder of mass 'm', radius 'r' and length 'l' about the longitudinal axis or polar axis is
- Amr²/2
- Bmr²/4
- Cmr²/6
- Dmr²/8
13.A lead ball with a certain velocity is made to strike a wall, it falls down, but rubber ball of same mass and with same velocity strikes the same wall, it rebounds. Select the correct reason from the following:
- ABoth the balls undergo an equal change in momentum
- BThe change in momentum suffered by rubber ball is more than the lead ball
- CThe change in momentum suffered by rubber ball is less than the lead ball
- DNone of the above
14.The coefficient of friction depends on
- AArea of contact
- BShape of surfaces
- CStrength of surfaces
- DNature of surface
15.Dynamic friction as compared to static friction is
- ASame
- BMore
- CLess
- DMay be less of more depending on nature of surfaces and velocity
16.The velocity ratio for the third system of pulleys is
- An
- Bn²
- C2n
- D2n – 1
17.If n = number of members and y = number of joints, then for a perfect frame, n = ?
- A1/2
- B2/3
- C3/2
- D2/4
18.The angle of inclination of the plane at which the body begins to move down the plane, is called
- AAngle of friction
- BAngle of repose
- CAngle of projection
- DNone of these
19.If ‘P’ is the force acting on the body, ‘m’ is the mass of the body and ‘a’ is the acceleration of the body, then according to Newton's second law of motion,
- AP + m.a = 0
- BP - m.a = 0
- CP × m.a = 0
- DP/m.a = 0
20.Two non-collinear parallel equal forces acting in opposite direction
- ABalance each other
- BConstitute a moment
- CConstitute a couple
- DConstitute a moment of couple