Description : A grinding wheel rotates at 3000 rpm. When power supply is cut off the wheel stops in 5 sec. The number of revolutions made by the wheel before coming to rest would be a.500 b.107 dynes c.250 d.3000 e.1000
Last Answer : c. 250
Description : A grinding wheel is rotating at 3000 rpm. When the switch is turned off the wheel stops in 10 seconds. The uniform deceleration of the wheel was a.1 rad/s2 b.31.4 rad/s2 c.4 rad/s2 d.62.8 rad/s2 e.10.4 rad/s2
Last Answer : b. 31.4 rad/s2
Description : A flywheel starting from rest and accelerating uniformly performs 25 revolutions in 5 sec. Its angular velocity in rpm after 10 seconds would be a.50 rpm b.20 rpm c.25 rpm d.60 rpm e.45 rpm
Last Answer : b. 20 rpm
Description : A wheel accelerates from rest with an acceleration of 6 rad/sec2. How many revolutions are experienced in 4 seconds? a.12.36 b.25.6 c.9.82 d.107 dynes e.7.64
Last Answer : e. 7.64
Description : A 3.2 m diameter balloon is filled with Helium. The total weight of balloon, gas and pay load is 10 kg kg. In an isothermal atmosphere having conditions identical to N.T.P. the balloon will rise to a height of about a.6000 m b.1500 m c.3000 m d.2000 m e.1000 m
Last Answer : a. 6000 m
Description : A wheel 8 mts in diameter coasts to rest from a speed of 800 rpm in 10 minutes. Its angular deceleration is a.308/min2 b.683 rad/min2 c.502 rad/min2 d.107 dynes e.809 rad/min2
Last Answer : c. 502 rad/min2
Description : A flywheel on a motor goes from rest to 1000 rpm in 6 sec. The number of revolutions made is nearly equal to (A) 25 (B) 50 (C) 100 (D) 250
Last Answer : (B) 50
Description : A man pulls a cart with 100 N force from rest with an acceleration of 10 m/sec2 for 10 seconds. The work done by him is a.500 KJ b.50.96 KJ c.101.92 KJ d.None of the above e.Tapered bearing
Last Answer : a. 500 KJ
Description : A hammer gains 50 Ns momentum in 0.05 sec. The average force on the hammer will be a.500 N b.2000 N c.1500 N d.107 dynes e.1000 N
Last Answer : e. 1000 N
Description : A 2 m long shaft rotates about one end at 20 rad/s. It begins to accelerate with ? = 10 rads/s2. After how long, in seconds, will the velocity of the free end reach 100 m/s? a.3 b.107 dynes c.5 d.6 e.7
Last Answer : a. 3
Description : The torque of 50 Nm is applied on the wheel operating a valve. If the wheel is rotated through two revolutions, work done in Newton-metres is given by a.628 b.107 dynes c.314 d.25 e.100
Last Answer : a. 628
Description : The number of revolutions through which a pulley will rotate from rest if its angular acceleration is increased uniformly from zero to 12 rad per sec2 during 4 sec and then uniformly decreased to 0 rad per sec2 during the next 3 sec would be a.46.4 b.26.74 c.11.6 d.3.2 e.17.7
Last Answer : b. 26.74
Description : If a particle charges its angular velocity from 30 to 35 rpm in 20 seconds then it has angular acceleration of a.107 dynes b.30 rev/min2 c.10 rev/min2 d.20 rev/min2 e.15 rev/min2
Last Answer : e. 15 rev/min2
Description : An electric motor drives a windless which hauls up a crate A of weight W = 500 kg up an inclined plane through a height of 10 m in 2 minutes. The torque acting on the windless is 25 kgm and the drum of the ... The efficiency of the inclined plane would be a.0.41 b.0.61 c.0.265 d.0.5305 e.0.66
Last Answer : d. 0.5305
Description : What is the total acceleration of a point on the rim of a flywheel 4 mts in diameter 0.6 see after it has started from rest if it accelarates uniformly from rest to 2000 rpm in 20 secs. a.68.9 mts/sec2 b.102.6 mts/sec2 c.78.94 mts/sec2 d.107 dynes e.33.2 mts/sec2
Last Answer : c. 78.94 mts/sec2
Description : A 4 pole lap wound dc shunt motor rotates at the speed of 1500 rpm, has a flux of 0.4 mWb and the total number of conductors are 1000. What is the value of emf? (A) 100 Volts. (B) 0.1 Volts. (C) 1 Volts. (D) 10 Volts.
Last Answer : Ans: D Given N = 1500 rpm, Φ = 0.4 mWb, Z = 1000, P = 4, & A= 4 Therefore, Eb = NΦPZ / 60 A = 1500 x 0.4 x 4 x 1000 x 10^-3 / 60 x 4 = 60/6 = 10 volts
Description : A 100 kg flywheel having a radius of gyration of 1 m is rotating at 1000 rpm. The angular momentum of the flywheel about its axis of rotation, in kg m2/s is a.1000 b.107 dynes c.10000 d.10470 e.5235
Last Answer : d. 10470
Description : A machine requires an effort of 10 kg to lift a load of 250 kg and an effort of 13 kg for a load of 400 kg. The effort required to lift a load of 500 kg will be a.25 kg b.107 dynes c.15 kg d.35 kg e.45 kg
Last Answer : c. 15 kg
Description : A force of 100 Newtons acts for 0.5 seconds on a body of mass 20 kg which is initially at rest. The velocity attained by the body is a.20 m/s b.5 m/s c.2.5 m/s d.0.5 m/s e.107 dynes
Last Answer : c. 2.5 m/s
Description : A car travelling at a speed of 60 km/hour is braked and comes to rest 6 seconds after the brakes are applied. The minimum coefficient of driction between the wheels and the road would be a.0.107 b.0.3 c.0.283 d.0.417 e.0.5
Last Answer : c. 0.283
Description : The length of Seconds Pendulum is a.992 mm b.999 mm c.994 mm d.995 mm e.1000 mm
Last Answer : c. 994 mm
Description : Two Pelton turbines A and B have the same specific speed and are working under the same head. Turbine A produces 400 kW at 1000 rpm. If turbine B produces 100kW, then its rpm is (a) 4000 (b) 2000 (c) 1500 (d) 3000
Last Answer : (b) 2000
Description : An automobile is travelling at 25 m/s. It takes 0.3 second to apply the brakes after which the deceleration is 6 m/s2. How far, in meters, does the automobile travel before it stops? a.45 b.107 dynes c.40 d.50 e.60
Last Answer : e. 60
Description : A flywheel rotating at 5 revolutions per second is brought to rest by a constant torque in 10 seconds. How many revolutions does the flywheel make while coming to a stop? w) 25 x) 50 y) 75 z) 100
Last Answer : ANSWER: W -- 25
Description : The resultant of a force acting on a body will be zero, if the body a.Rotates with uniform acceleration b.Moves along a curved path c.Rotates d.Does not rotate e.Rotates with uniform deceleration
Last Answer : d. Does not rotate
Description : The piston of a steam engine moves in S.H.M. The crank rotates at 180 r.p.m. and the stroke length is 2 metres. The linear velocity of the piston when it is at a distance of 1 metre from the centre is a.8.88 m/sec b.16.32 m/sec c.5.88 m/sec d.8.16 m/sec e.Zero
Last Answer : e. Zero
Description : Coating thickness in case of galvanising of steel sheet generally corresponds to the deposition of __________ gms of zinc per m2 of steel strip. (A) 5-10 (B) 1000-1500 (C) 120-500 (D) 1500-3000
Last Answer : Option C
Description : A flywheel 200 cm in diameter is rotating at 100 rpm. A point on the rim of the flywheel will not have a.angular velocity b.centripental acceleration c.tangential acceleration d.all of the above e.107 dynes
Last Answer : c. tangential acceleration
Description : In a slider crank mechanism, the crank is rotating at 200 rpm. If length of connecting rod is 8 mts and crank shaft is 2 mts, velocity of crosshead at 30? rotation of crank shaft equals. a.30.2 m/s b.33.2 m/s c.35.8 mts/s d.107 dynes e.25.5 m/s
Last Answer : e. 25.5 m/s
Description : A flywheel 200 cm in diameter is rotating at 100 rpm. A point one the rim of the flywheel will not have a.angular velocity b.centripetal acceleration c.tangential acceleration d.all of the above e.107 dynes
Last Answer : a. angular velocity
Description : The limiting force of fiction is a.The friction force acting on a body when it is in motion b.The value of friction force which stops the movement of the body c.The value of friction force which ... d.The friction force acting when the body is just about to move e.Double of the normal friction
Last Answer : d. The friction force acting when the body is just about to move
Description : When a train is rounding a curve to prevent side thrust on the wheel flanges of cars a.Opposite thrust is created to counter balance this thrust b.Guide rail sections are provided to take care of ... are provided in the train d.Outside rails are realised e.Rail section is made thick on curvature
Last Answer : d. Outside rails are realised
Description : A projectile is shot straight up with vo = 40 m/s. After how many seconds will it return if drag is neglected? a.6 b.107 dynes c.4 d.10 e.8
Last Answer : e. 8
Description : A flywheel weighs 400 kg and has a radius of gyration of 30 cm about its axis of rotation. It is mounted on a shaft subjected to a moment of 40 kgm. If the flywheel starts from restits speed after 3 seconds wil be a.10.9 rad/sec b.19.0 rad/sec c.51.2 rad/sec d.3.33 rad/sec e.16.35 rad/sec
Last Answer : d. 3.33 rad/sec
Description : How many revolutions will a turntable that rotates through an angle of 3 over 2 pi in one second make in 60 seconds?
Last Answer : I guess you mean 3 pi over 2, ie 3Ï€/2 though it may have been given to you as (3/2)Ï€ To solve this, find the total angle turned in 60 seconds and divide by the angle in a whole ... radians = 90Ï€/2Ï€ revolutions = 45 revolutions (45 rpm - the figure calculated - was the standard for a single).
Description : In a single threaded worm and worm wheel the number of teeth on the worm wheel is 60. The diameter of the effort wheel is 12 cm and that of load drum is 8 cm. The velocity ratio will be a.90 b.120 c.60 d.45 e.107 dynes
Last Answer : a. 90
Description : In a single threaded worm and worm wheel the number of teeth on the worm wheel is 80. The diameter of the effort wheel is 12 cm and that of load drum is 8 cm. The velocity ratio will be a.60 b.45 c.120 d.107 dynes e.90
Last Answer : c. 120
Description : A particle starts from rest and moves in a straight line whose equation of motion is given by S = 2t3 - t2 - 1. The acceleration of the particle after one sec will be a.6 m/sec2 b.4 m/sec2 c.12 m/sec2 d.10 m/sec2 e.8 m/sec2
Last Answer : d. 10 m/sec2
Description : Power required for a train weighing 200 Mg to move at a uniform speed of 60 Kmph up an incline of 1 in 200 is (Resistance due to friction is negligible) a.16.67 KW b.163.5 KW c.1000 KW d.9810 KW e.Tapered bearing
Last Answer : b. 163.5 KW
Description : The motion of a bicycle wheel is a.Curvilinear b.Translatory c.Linear d.Rotary as well as translatory e.Rotary
Last Answer : d. Rotary as well as translatory
Description : Which of the following is not a lever of the first order? a.Pair of Smith's tongs b.Wheel barrow c.Ordinary balance d.Pair of scissors e.107 dynes
Last Answer : b. Wheel barrow
Description : Instantaneous centre for a rolling wheel on a straight track will be at a.107 dynes b.A c.B d.C e.D
Last Answer : e. D
Description : A ball weighing 250 gm is thrown vertically upwards with a velocity of 980 cm/sec. The time that the ball will take to return back to earth would be a.1 sec b.4 sec c.2 sec d.5 sec e.3 sec
Last Answer : c. 2 sec
Description : The gravitational field at the surface of the moon is one sixth of that at the surface of the earth. A 72 kg man weighs on the surface of the moon a.137.7 N b.250 c.72 N d.420 N e.117.7 N
Last Answer : e. 117.7 N
Description : A jet of water of cross-sectional area 20 sq. cm impinges on a plate at an angle of 60? with a velocity of 10 m/sec. Neglecting the friction between the jet and plate (density of water 1000/9.81 kgm-1 sec2 per cubic meter), the ... a.15 - 20 kg b.20 - 25 kg c.5 - 10 kg d.25 - 30 kg e.10 - 15 kg
Last Answer : a. 15 - 20 kg
Description : A locomotive of weight 100 tonnes is attached to train of wagons weighing 1000 tonnes. The locomotive pulls the wagons with a constant velocity of 36 km/hour. When the coupling between the train and wagons breaks, the wagons roll on 95 m in ... would be a.0.36 m b.0.44 m c.0.77 m. d.0.5 m e.0.66 m
Last Answer : d. 0.5 m
Description : A body weighing one tonne falls through 8 cm on to a spring of stiffness 500 kg/cm the spring will be compressed through a.8 cm b.6 cm c.4 cm d.10 cm e.12 cm
Last Answer : a. 8 cm
Description : The angular velocity of seconds hand of a watch is a.0.01745 sec-1 b.0.00001745 sec-1 c.0.0001745 sec-1 d.0.001745 sec-1 e.0.1047 sec-1
Last Answer : d. 0.001745 sec-1
Description : A stone is dropped into a deep shaft without any initial velocity. The sound of the stone hitting the bottom is heard after 4 seconds. If the velocity of sound is 330 m/sec the depth of the shaft will be a.33.1 m b.660 m c.165 m d.66.2 m e.330 m
Last Answer : d. 66.2 m
Description : A rigid body is suspended vertically at a point and oscillates with a small amplitude under the action of the force of gravity. Such an arrangement is called a.Simple pendulum b.Rigid pendulum c.Second's pendulum d.Compound pendulum e.Newton's pendulum
Last Answer : d. Compound pendulum