Machines and Graphics Multiple Choice Questions and Answers

1 A cylinder will slip on an inclined plane of inclination 0 if the coefficient of static friction between plane and cylinder is

A less than (1/3) tan 0

B less than (2/3) tan 0

C less than (1/3) sin 6

D less than (2/3) sin 6

View Answer

Answer: less than (1/3) tan 0

2 A solid cylinder of mass M and radius R rolls down an inclined plane without slipping. The acceleration of center of mass of rolling cylinder is

A (1/3) g sinB

B (2/3) g cos 9

C (2/3) g sin 0

D g sin 9

View Answer

Answer: (2/3) g sin 0

3 The total kinetic energy of a hoop of mass 2 kg and radius 4 m sliding with linear velocity 8 m/sec and angular velocity 5 radian/sec is

A 64 J

B 400 J

C 464 J

D 89 J

View Answer

Answer: 464 J

4 A uniform pyramid and a uniform prism of same height lie with their base on the surface. Which is more stable ?

A pyramid

B prism

C both equally stable

D None of these

View Answer

Answer: pyramid

5 The following is in unstable equilibrium

A a uniform solid cone resting on a generator on a smooth horizontal plane

B a uniform solid cone resting on its base on a horizontal plane

C a solid cube resting on one edge

D a satellite encircling the earth

View Answer

Answer: a solid cube resting on one edge

6 The resultant of two forces P and Q is R. If Q is doubled, the new resultant is perpendicular to P. Then,

A P = R

B Q = R

C P = Q

D None of the above is correct

View Answer

Answer: Q = R

7 The angles between two forces to make their resultant a minimum and a maximum respectively are

A 0° and 90°

B 180° and 90°

C 90° and 180°

D 180° and 0°

View Answer

Answer: 180° and 0°

8 A force P of 50 N and another force Q of unknown magnitude act at 90° to each other. They are balanced by a force of 130 N. The magnitude of Q is

A 60 N

B 80 N

C 100 N

D 120 N

View Answer

Answer: 120 N

9 A rod AB carries three loads of 30 N, 70 N and 100 N at distances of 20 mm, 90 mm and 150 mm respectively from A. Neglecting the weight of the rod, the point at which the rod will balance is

A 109.5 mm from A

B 119.5 mm from A

C 125.5 mm from A

D 132.5 mm from A

View Answer

Answer: 109.5 mm from A

10 If the resultant of two forces has the same magnitude as either of the force, then the angle between the two forces is

A 30°

B 45°

C 60°

D 120°

View Answer

Answer: 120°

11 When two forces, each equal to P, act at 90° to each other, then the resultant will be

A P

B PV2

C P/V2

D 2P

View Answer

Answer: PV2

12 A block in the shape of a parallelopiped of sides lm x 2m x 3m lies on the surface. Which of the faces gives maximum stable block ?

A 1 m x 2 m

B 2 m x 3 m

C 1 m x 3m

D equally stable on all faces

View Answer

Answer: 2 m x 3 m

13 Minimum potential energy of a system will be in the position of

A stable equilibrium

B unstable equilibrium

C neutral equilibrium

D all of the above

View Answer

Answer: stable equilibrium

14 A symmetrical body is rotating about its axis of symmetry, its moment of inertia about the axis of rotation being 2 kg -m2 and its rate of rotation 2 revolutions/see. The angular momentum of the body in kg-m2/sec is

A 4

B 6 7i

C 8TC

D 8

View Answer

Answer: 8TC

15 The ratio of the speed of a rolling cylinder to the speed of sliding cylinder is

A less than 1

B equal to 1

C between 1 and 2

D greater than 2

View Answer

Answer: less than 1

16 A hoop of radius 3 m weighs 100 kg. It rolls along a horizontal floor so that at its centre of mass has a speed of 200 mm/sec, . The work required to stop the hoop is

A 2 J

B 4 J

C 6 J

D 8 J

View Answer

Answer: 4 J

17 A solid sphere of mass M and radius R rolls down a plane inclined at 0 with the horizontal. The acceleration of sphere is

A (1/3) g sin0

B (2/5) g sin 0

C (3/7) g sin 0

D (5/7) g sin0

View Answer

Answer: (5/7) g sin0

18 Rate of change of angular momentum is equal to

A force

B torque

C linear momentum

D impulse

View Answer

Answer: torque

19 If the angular distance, 0 = 2t3 - 3t2, the angular acceleration at t = 1 sec. is

A 1 rad/sec2

B 4 rad/sec2

C 6 rad/sec2

D 12 rad/sec2

View Answer

Answer: 6 rad/sec2

20 A particle moves in a straight line and its position is defined by the equation x = 6 t2 - t3 where t is expressed in seconds and x in meters. The maximum velocity during the motion is

A 6 m/sec

B 12 m/sec

C 24 m/sec

D 48 m/sec

View Answer