# Engineering Mechanics 4

First Year Engineering Common to all Branches: Engineering Mechanics 4

Subject: Engineering Mechanics 4

Part 4: List for questions and answers of Engineering Mechanics

Q1. The matter contained in a body, is called
a) impulsive force
b) mass
c) weight
d) momentum

Q2. The law of the machine is(where P = Effort applied to lift the load, m = A constant which is equal to the slope of the line, W = Load lifted, and C = Another constant which represents the machine friction.)
a) P = mW – C
b) P = m/W + C
c) P = mW + C
d) P = C – mW

Q3 According to lami’s theorem
a) the three forces must be equal
b) the three forces must be at 120° to each other
c) the three forces must be in equilibrium
d) if the three forces acting at a point are in equilibrium, then each force is proportional to the sine of the angle between the other two

Q4. The centre of gravity of a quadrant of a circle lies along its central radius (r) at a distance of
a) 0.5r
b) 0.6r
c) 0.7r
d) 0.8r

Q5. Which of the following are vector quantities?
a) Angular displacement
b) Angular velocity
c) Angular acceleration
d) all of these

Q6. The maximum mechanical advantage of a lifting machine is
a) + m
b) m
c) 1 / m
d) m

Q7. A machine having an efficiency greater than 50%, is known as
a) reversible machine
b) non-reversible machine
c) neither reversible nor non-reversible machine
d) ideal machine

Q8. An ideal machine is one whose efficiency is
a) between 60 and 70 %
b) between 70 and 80%
c) between 80 and 90%
d) 100%

Q9. The energy possessed by a body, for doing work by virtue of its position, is called
a) potential energy
b) kinetic energy
c) electrical energy
d) chemical energy

Q10. Moment of inertia is the
a) second moment of force
b) second moment of area
c) second moment of mass
d) all of these

Q11. The coefficient of restitution for inelastic bodies is
a) zero
b) one
c) between zero and one
d) more than one

Q12. The term ‘centroid’ is
a) the same as centre of gravity
b) the point of suspension
c) the point of application of the resultant of all the forces tending to cause a body to rotate about a certain axis
d) none of the above

Q13. In order to completely specify angular displacement by a vector, it must fix
a) direction of the axis of rotation
b) magnitude of angular displacement
c) sense of angular displacement
d) all of these

Q14. The acceleration of a body sliding down an inclined surface is
a) g sin θ
b) g cos θ
c) g tan θ
d) none of these

Q15. If a body is acted upon by a number of coplaner non-concurrent forces, it may
a) rotate about itself without moving
b) move in any one direction rotating about itself
c) be completely at rest
d) all of these

Q16. The velocity ratio of a simple wheel and axle with D and d as the diameters of effort wheel and load axle, is
a) D + d
b) D – d
c) D x d
d) D / d

Q17. The unit of force in S.I. system of units is
a) dyne
b) kilogram
c) newton
d) watt

Q18. A ladder is resting on a rough ground and leaning against a smooth vertical wall. The force of friction will act
a) downward at its upper end
b) upward at its upper end
c) zero at its upper end
d) perpendicular to the wall at its upper end

Q19. Joule is the unit of
a) force
b) work
c) power
d) velocity

Q20. The centre of gravity a T-section 100 mm x 150 mm x 50 mm from its bottom is
a) 50mm
b) 75mm
c) 87.5mm
d) 125mm

Part 4 : List for questions and answers of Engineering Mechanics