Applied Mechanics and Graphic Statics 1000+ MCQ with answer for ISRO Recruitment

1. A stone is thrown up a slope of inclination 60° to the horizontal. At what angle to the slope must the stone be thrown so as to land as far as possible from the point of projection?
A. 15°
B. 30°
C. 45°
D. 75°
Answer : A

2. If the angle of projection is double the angle of inclination (?) of the plane on which particle is projected, the ratio of times of flight up the inclined plane and down the inclined plane, will be
A. ½ cos ?
B. ½ sin ?
C. ½ tan ?
D. 2 cos ?
Answer : A

3. Two particles have been projected at angles 64° and 45° to the horizontal. If the velocity of projection of first is 10 m/sec, the velocity of projection of the other for equal horizontal ranges is
A. 9.3 m/sec
B. 8.3 m/sec
C. 7.3 m/sec
D. 6.3 m/sec
Answer : A

4. The resultant of the forces acting on a body will be zero if the body
A. Rotates
B. Moves with variable velocity in a straight line
C. Moves along a curved path
D. Does not move at all
Answer : D

5. The diagram showing the point of application and line of action of forces in their plane is called
A. Vector diagram
B. Space diagram
C. Force diagram
D. Funicular diagram
Answer : B

6. One Joule is equivalent to
A. 9.81 Newton metre
B. 1 Newton metre
C. 1 kg wt metre
D. 1 dyne metre
Answer : B

7. A particle moving with a simple harmonic motion, attains its maximum velocity when it passes
A. The extreme point of the oscillation
B. Through the mean position
C. Through a point at half amplitude
D. None of these
Answer : B

8. For a self-locking machine, the efficiency should be
A. Less than 60%
B. 50 %
C. More than 50%
D. None of these
Answer : A

9. A load of 500 kg was lifted through a distance of 13 cm. by an effort of 25 kg which moved through a distance of 650 cm. The velocity ratio of the lifting machine is
A. 50
B. 55
C. 60
D. 65
Answer : A

10. Pick up the correct statement from the following:
A. If two equal and perfectly elastic smooth spheres impinge directly, they interchange their velocities
B. If a sphere impinges directly on an equal sphere which is at rest, then a fraction ½(1 - e2) the original kinetic energy is lost by the impact
C. If two equal spheres which are perfectly elastic impinge at right angles, their direction after impact will still be at right angles
D. All the above
Answer : D

11. Varingons theorem of moments states
A. Arithmetical sum of the moments of two forces about any point, is equal to the moments of their resultant about that point
B. Algebraic sum of the moments of two forces about any point, is equal to the moment of their resultant about that point
C. Arithmetical sum of the moments of the forces about any point in their plane, is equal to the moment of their resultant about that point
D. Algebraic sum of the moments of the forces about any point in their plane, is equal to the moment of their resultant about that point
Answer : D

12. A system of coplanar forces is in equilibrium when
A. Force polygon closes
B. Funicular polygon closes
C. Both force polygon and funicular polygon close
D. All the forces are concurrent
Answer : C

13. The Centre of gravity of a 10 × 15 × 5 cm T-section from its bottom, is
A. 7.5 cm
B. 5.0 cm
C. 8.75 cm
D. 7.85 cm
Answer : C

14. A body A of mass 6.6 kg which is lying on a horizontal platform 4.5 m from its edge is connected to the end of a light string whose other end is supporting a body of mass 3.2 kg as shown in below figure. If the friction between the platform and the body A is 1/3, the acceleration is
A. 0.5 m/sec²
B. 0.75 m/sec²
C. 1.00 m/sec²
D. 1.25 m/sec²
Answer : C

15. If two equal forces of magnitude P act at an angle ?, their resultant, will be
A. P cos ?/2
B. 2P sin ?/2
C. P tan ?/2
D. 2P cos ?/2
Answer : D

16. A weight W is suspended at the free end of a light member hinged to a vertical wall. If the angle of inclination of the member with the upper wall is ?°, the force introduced in the member, is
A. W sec ?
B. W cos ?
C. W sin ?
D. W cosec ?
Answer : A

17. Pick up the correct statement from the following for the structure shown in below figure.

A. The horizontal reaction at A is 2 ?3t ?
B. The horizontal reaction at C is 2 ?3t ?
C. The vertical reaction at A is zero
D. All the above
Answer : D

18. Time of flight of a projectile on a horizontal plane, is
A. 2u sin?/g
B. 2u cos?/g
C. 2u tan?/g
D. 2u cot?/g
Answer : A

19. If a bod is acted upon by a number of coplanar non-concurrent forces, it may
A. Rotate about itself without moving
B. Move in any one direction
C. Move in any one direction rotating about itself
D. All the above
Answer : D

20. The moment of inertia of a hollow circular section whose external diameter is 8 cm and internal diameter is 6 cm, about centroidal axis, is
A. 437.5 cm⁴
B. 337.5 cm⁴
C. 237.5 cm⁴
D. 137.5 cm⁴
Answer : D

21. If A is the amplitude of particle executing simple harmonic motion, then the total energy E of the particle is
A. Proportional to A
B. Proportional to A²
C. Proportional to 1/A²
D. Independent of A
Answer : B

22. If the horizontal range is 2.5 times the greatest height, the angle of projection of the projectile, is
A. 57°
B. 58°
C. 59°
D. 60°
Answer : B

23. For a given velocity of a projectile, the range is maximum when the angle of projection is
A. 30°
B. 45°
C. 90°
D. 0°
Answer : B

24. A particle is dropped from the top of a tower 60 m high and another is projected upwards from the foot of the tower to meet the first particle at a height of 15.9 m. The velocity of projection of the second particle is
A. 16 m/sec
B. 18 m/sec
C. 20 m/sec
D. 22 m/sec
Answer : C

25. The graphical method of determining the forces in the members of a truss is based on
A. Method of joint
B. Method of section
C. Either method
D. None of the two methods
Answer : A

26. Newton's law of Collision of elastic bodies states that when two moving bodies collide each other, their velocity of separation
A. Is directly proportional to their velocity of approach
B. Is inversely proportional to their velocity of approach
C. Bears a constant ratio to their velocity of approach
D. Is equal to the sum of their velocities of approach
Answer : C

27. Total no of instantaneous centres of a machine having n links, is
A. n/2
B. n
C. (n - 1)
D. n (n - 1)/2
Answer : D

28. The centre of gravity of a quadrant of a circle lies along its central radius at a distance of
A. 0.2 R
B. 0.4 R
C. 0.3 R
D. 0.6 R
Answer : D

29. The motion of a bicycle wheel is
A. Translatory
B. Rotary
C. Rotary and translatory
D. Curvilinear
Answer : C

30. If the velocity of projection is 4 m/sec and the angle of projection is ?°, the maximum height of the projectile from a horizontal plane, is
A. u² cos² ?/2g
B. u² sin² ?/2g
C. u² tan² ?/2g
D. u² sin 2?/2g
Answer : B

31. Parallelogram Law of Forces states, if two forces acting simultaneously on a particle be represented in magnitude and direction by two adjacent sides of a parallelogram, their resultant may be represented in magnitude and direction by
A. Its longer side
B. Its shorter side
C. The diagonal of the parallelogram which does not pass through the point of intersection of the forces
D. The diagonal of the parallelogram which passes through the point of intersection of the forces
Answer : D

32. If two forces are in equilibrium, then the forces must (i) Be equal in magnitude (ii) Be opposite in sense (iii) Act along the same line The correct answer is
A. (i) and (ii)
B. (i) and (iii)
C. Only (i)
D. All (i), (ii) and (iii)
Answer : D

33. A stone is whirled in a vertical circle, the tension in the string, is maximum
A. When the string is horizontal
B. When the stone is at the highest position
C. When the stone is at the lowest position
D. At all the positions
Answer : C

34. For the given values of initial velocity of projection and angle of inclination of the plane, the maximum range for a projectile projected upwards will be obtained, if the angle of projection is
A. ? = ?/4 - ?/2
B. ? = ?/2 + ?/2
C. ? = ?/2 - ?/2
D. ? = ?/4 - ?/2
Answer : B

35. A train weighing 196 tonnes experiences a frictional resistance of 5 11/22 per tonne. The speed of the train at the top of a down gradient 1 in 78.4 is 36 km/hour. The speed of the train after running 1 km down the slope, is
A. 5 ?10 m/sec
B. 10 ?5 m/sec
C. 5 ?3 m/sec
D. 3 ?5 m/sec
Answer : A

36. If the given forces P?, P?, P? and P? are such that the force polygon does not close, then the system will
A. Be in equilibrium
B. Always reduce to a resultant force
C. Always reduce to a couple
D. Both (A) and (C)
Answer : B

37. If l is the span of a light suspension bridge whos each cable carries total weight (w) and the central dip is y, the horizontal pull at each support, is
A. wl/4y
B. wl/8y
C. wl/2y
D. wl
Answer : B

38. The angular speed of a car taking a circular turn of radius 100 m at 36 km/hr will be
A. 0.1 rad/sec
B. 1 rad/sec
C. 10 rad/sec
D. 100 rad/sec
Answer : A

40. The resolved part of the resultant of two forces inclined at an angle ? in a given direction is
A. Algebraic sum of the resolved parts of the forces in the direction
B. Arithmetical sum of the resolved parts of the forces in the direction
C. Difference of the forces multiplied by cosine ?°
D. Sum of the forces multiplied by the tangent ?°
Answer : A

41. A satellite moves in its orbit around the earth due to
A. Gravitational force
B. Centripetal force
C. Centrifugal force
D. None of these
Answer : B

42. A particle moves along a straight line such that distance x traversed in t seconds is given by x = t2(t + 1), the acceleration of the particle, will be
A. 3t³ - 2t
B. 3t² + 2t
C. 6t - 2
D. 6t + 2
Answer : D

43. Three forces which act on a rigid body to keep it in equilibrium. The forces must be coplanar and
A. Concurrent
B. Parallel
C. Concurrent parallel
D. None of these
Answer : A

44. Select the correct statement
A. The body centrode rolls on the space centrode
B. The space centrode rolls on the body centrode
C. Both body and space centrodes may role on each other
D. The body centrode never touches space centrode
Answer : A

45. The moment of inertia of the shaded portion of the area shown in below figure about the X-axis, is

A. 229.34 cm4
B. 329.34 cm4
C. 429.34 cm4
D. 529.34 cm4
Answer : C

46. If a particle is projected inside a horizontal tunnel which is 554 cm high with a velocity of 60 m per sec, the angle of projection for maximum range, is
A. 8°
B. 9°
C. 10°
D. 11°
Answer : C

47. At a given instant ship A is travelling at 6 km/h due east and ship B is travelling at 8 km/h due north. The velocity of B relative to A is
A. 7 km/hrs
B. 2 km/hrs
C. 1 km/hrs
D. 10 km/hrs
Answer : D

48. Which of the following represents the state of neutral equilibrium?
A. A cube resting on one edge
B. A smooth cylinder lying on a curved surface
C. A smooth cylinder lying on a convex surface
D. None of the above
Answer : D

49. According to Law of Triangle of Forces
A. Three forces acting at a point, can be rep-resented by the sides of a triangle, each side being in proportion to the force
B. Three forces acting along the sides of a triangle are always in equilibrium
C. If three forces acting on a, point can be represented in magnitude and direction, by the sides of a triangle taken in order, these will be in equilibrium
D. If the forces acting on a particle be represented in magnitude and direction by the two sides of a triangle taken in order, their resultant will be represented in magnitude and direction by the third side of the triangle, taken in opposite order
Answer : D

50. The product of mass and velocity of a moving a body, is called
A. Moment
B. Momentum
C. Power
D. Impulse
Answer : B