Machines and Graphics Multiple Choice Questions with Answers

61 The dimensions of centrifugal force are

A M1 L2 T2

B M'L'T1

C M'L'T2

D M'L-'T2

Answer: M'L'T2

62 A quantity measured in the C.G.S system of units has dimensions M"2L3 T3/2. What numerical factor would be required to convert the quantity to SI units ?

A 1

B 100

C 1/100

D 1/10000

View Answer

Answer: 1

63 In SI units, the units of force and energy are respectively

A Newton and watt

B Dyne and erg

C Newton and joule

D kg-wt and joule

View Answer

Answer: Newton and joule

64 The ratio of unit of force in gravitational system to that in absolute system is

A 1

B g

C 1/g

D none of the above

View Answer

Answer: g

65 A quantity whose dimensions are M2L2 T3 could be the product of

A Force And Pressure

B Mass And Power

C Energy And Velocity

D Force And Velocity

View Answer

Answer: Mass And Power

66 Joule is the unit of

A Power

B Impulse

C Work

D Momentum

View Answer

Answer: Impulse

67 The ratio of kinetic energy and potential energy of a simple harmonic oscillator, at a displacement equal to half its amplitude is given by

A 1:2

B 1:1

C 2:1

D 3:1

View Answer

Answer: 3:1

68 The maximum displacement of a particle executing S.H.M. corresponds to

A zero potential energy and maximum kinetic energy

B zero kinetic energy and maximum potential energy

C maximum kinetic energy and maxi-mum potential energy

D minimum kinetic energy and minimum potential energy

View Answer

Answer: zero kinetic energy and maximum potential energy

69 The time period of a simple pendulum depends on i) mass of suspended particle ii) length of the pendulum iii) acceleration due to gravity The correct answer is

A only (i)

B both (ii) and (iii)

C both (i) and (iii)

D all are correct

View Answer

Answer: both (ii) and (iii)

70 The angle of projection at which the horizontal range and maximum height of a projectile are equal to

A 45°

B tan-1 (2)

C tan-' (4)

D tan"1 (1/4)

View Answer

Answer: tan-' (4)

71 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°

View Answer

Answer: 15°

72 A circular disc rotates at n rpm. The angular velocity of a circular ring of same mass and radius as the disc and to have the same angular momentum is

A n rpm

B n/2 rpm

C n/4 rpm

D 2n rpm

View Answer

Answer: n/2 rpm

73 A flywheel of moment of inertia 20 kg-m" is acted upon by a tangential force of 5 N at 2 m from its axis, for 3 seconds. The increase in angular velocity in radian persecond is

A 1/2

B 3/2

C 2

D 3

View Answer

Answer: 3/2

74 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

View Answer

Answer: The body centrode rolls on the space centrode

75 Instantaneous center is at infinity when the angular velocity is

A constant

B zero

C maximum

D minimum

View Answer

Answer: zero

76 A 2 m long ladder rests against a wall and makes an angle of 30° with the horizontal floor. Where will be the instantaneous center of rotation when the ladder starts slipping ? i) 1.0 in from the wall ii) 1.732 m from the wall iii) 1.0 m above the floor iv) 1.732 m above the floor The correct answer is

A (i) and (iii)

B (i) and (iv)

C (ii) and (iii)

D (ii) and (iv)

View Answer

Answer: (ii) and (iv)

77 The angle of projection at which the horizontal range and maximum height of a projectile are equal to

A 36°

B 45°

C 56°

D 76°

View Answer

Answer: 76°

78 The maximum value of the horizontal range for a projectile projected with a velocity of 98 m/sec is

A 98 m

B 490 m

C 980 m

D 1960 m

View Answer

Answer: 980 m

79 A projectile has maximum range of 40 m on a horizontal plane. If angle of projection is a and the time of flight is 1 second, then sin a must be about

A 1/4

B 1/3

C 1/2

D 1/5

View Answer

Answer: 1/4

80 If the direction of projection bisects the angle between the vertical and the inclined plane, then the range of projectile on the inclined plane is

A zero

B maximum

C minimum

D unpredictable

View Answer