Description : A car is travelling at 90 km/hour on a rough road where the coefficient of friction between the road and the tyre is 0.5. The distance the car will skid before stopping when the brakes are jammed suddenly would be a.127.4 m b.95.55 m c.63.7 m d.31.85 m e.90 m
Last Answer : c. 63.7 m
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 : If you want to stop the car in the shortest distance on an icy road, you should a.107 dynes b.not apply the brakes c.pump' the brakes d.push hard the brakes to lock the wheels e.push just hard enough to prevent slipping
Last Answer : e. push just hard enough to prevent slipping
Description : Static friction is always a.greater than the dynamic driction b.either greater or more than the dynamic friction c.less than the dynamic friction d.107 dynes e.equal to the dynamic friction
Last Answer : a. greater than the dynamic driction
Description : An automobile weighing 2800 lb and travelling at 30 miles/hr, hits a depression in the road which has a radius of curvature of 50 ft. What is the total force to which springs are subjected. a.8230 lb b.6170 lb c.2800 ib d.107 dynes e.3280 lb
Last Answer : b. 6170 lb
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 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 train travels between two stations 15 km apart in 18 minutes. If the train accelerates for a part of journey uniformly followed by uniform retardation, the maximum speed attained by the train during the journey will by a.125 km/hr b.107 dynes c.80 km/hr d.100 km/hr e.60 km/hr
Last Answer : d. 100 km/hr
Description : A train travels between two stations 15 km, apart in 18 minutes. If the train accelerates for a part of journey uniformly followed by uniform relardation, the maximum speed attained by the train, during, the journey, will be a.60 km/hr b.80 km/hr c.125 km/hr d.100 km/hr e.107 dynes
Description : A man weighing 60 kg jumps on a vehicle of weight 240 kg moving with a velocity of 36 km/hours. The velocity of the vehicle after the man has jumped would be a.Less than 3.6 km/hour b.3.6 km/hour c.More than 3.6 km/hour d.4.5 km/hour e.None of the above
Last Answer : a. Less than 3.6 km/hour
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 : 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 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 : 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 ball is dropped from a height of 2.25 m on a smooth floor and it rises to a height of 1 m after the first bounce. The coefficient of restitutions between the ball and the floor is a.107 dynes b.0.33 c.0.44 d.0.57 e.0.67
Last Answer : e. 0.67
Description : A satellite orbits the earth 200 km above the surface. What speed, in m/s, is necessary for a circular orbit? The radius of the earth is 6400 km and g = 9.2 m/s2 a.7200 b.6600 c.7800 d.6000 e.107 dynes
Last Answer : c. 7800
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 : Kinetic friction is a.Maximum value of frictional force when a body is about to move b.Friction between two well lubricated bodies c.Friction force acting when the body is in motion d.Driction force which keeps a body in motion e.None of the above
Last Answer : c. Friction force acting when the body is in motion
Description : The mass, in kg, of the earth if its radius is 6400 km, will be a.6 x 1024 b.6 x 1025 c.107 dynes d.6 x 1023 e.6 x 1022
Last Answer : a. 6 x 1024
Description : A boy sitting in a rail road car throws a ball straight up into the air. The ball will fall back into his hands when the rail road car is a.moving at constant velocity b.accelerating ... inclined plane, while another identical block B is released for free fall from the same height e.decelerating
Last Answer : a. moving at constant velocity
Description : A particle of mass M moves towards right with a velocity 2 V along the x-axis and another of mass 2 M with a velocity V towards left (- x axis). After the collision (they stick together on colliging) ... a.come to rest b.107 dynes c.move towards right d.may move in any direction e.move towards left
Last Answer : c. move towards right
Description : A uniform cylinder of weight W is rolling while slipping on a rough horizontal surface under the influence of a horizontal force. The force of friction between the cylinder and the surface is a. ... on the acceleration of the cylinder d.107 dynes e.Proportional to the coefficient of static friction
Last Answer : c. Determinate but depends on the acceleration of the cylinder
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 : Stopping distance of vehicles : When brakes are applied to a moving vehicle, the distance it travels before stopping is called stopping distance. It is an important factor for road safety and depends on ... the brake with the deceleration of 5m/s2. Find the stopping distance of the car -Science
Last Answer : Here u=72 km/hr = 72×10003600m/s=2072×10003600m/s=20 m/s , v=0 a= -5 m/s2 Now using the relation v2=u2+2asv2=u2+2as 0=(20)2+2×(−5)×s0=(20)2+2×(−5)×s s=40ms=40m
Description : The excape velocity for the moon is nearly a.5 km/s b.11.2 km/s c.107 dynes d.2.4 km/s e.1.1 km/s
Last Answer : d. 2.4 km/s
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 : Let the only force acting on two bodies be their mutual interactions. If both bodies start from rest, the distances travelled by each will be a a.proportional to the respective masses of the ... masses of the bodies e.inversely proportional to the square of the respective masses of the bodies
Last Answer : c. inversely proportional to the respective masses of the bodies
Description : A plane is inclinea at angle ? to horizontal. If a body can just rest on a plane, determine the least force to draw the body up the plance a.W sin2? b.2 W cos2? c.107 dynes d.W cos2? e.2 W sin2?
Last Answer : a. W sin2?
Description : A couple applied to a flywheel of mass 5 kg and of radius of gyration 20 cm produces an angular acceleration of 4 radians/sec2. The torque applied in dyne cm is a.8 x 104 b.8 x 106 c.8 x 107 d.8 x 108 e.8 x 1010
Last Answer : b. 8 x 106
Description : In a tug of war, five men pull a rope to the left at A and six moen pull the rope at B. A weight of 5 kg is hung vertically from the centre of the rope. In order that the rope AB be horizontal ... to be applied at both ends d.the force required on A must not be equal to that on B e.107 dynes
Last Answer : c. infinite force will be required to be applied at both ends
Description : A particle inside a hollow sphere of internal radius r with coefficient of friction 1/?3 can rest upto height of a.0.18 r b.0.435 r c.0.25 r d.0.134 r e.0.125 r
Last Answer : d. 0.134 r
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 value of acceleration due to gravity is 980 cm/sec2. Its value in meter per (hour)2 will be a.1.27 x 108 b.127 c.1270 d.1.27 x 107 e.1270000
Last Answer : a. 1.27 x 108
Description : A ball of mass 1 kg moving with a velocity of 2 m/sec collides directly with a stationary ball of mass 2 kg. If the first ball comes to rest after the impact the velocity of second ball after impact will be a.1.5 m/sec b.0.5 m/sec c.Zero d.2 m/sec e.1.0 m/sec
Last Answer : e. 1.0 m/sec
Description : The breaking strength of a rope is 400 N. A fireman weighing 60 kg slides down the rope. The rope will break if a.107 dynes b.the acceleration is 7.5 m/s2 c.the acceleration is 1.2 m/s2 d.the acceleration is 3.1 m/s2 e.the slides with an acceleration of 15 m/s2
Last Answer : c. the acceleration is 1.2 m/s2
Description : The tension T1 will be a.5 N b.20 N c.60 N d.10 N e.107 dynes
Last Answer : d. 10 N
Description : A horizontal load of 120 kg/mt is to be carried by a cable suspended between supports at same level and 60 mts apart. If the maximum permissible tension is 36,000 kg the required length of cable is a.63.3 mets b.62.5 mts c.60.8 mts d.107 dynes e.60.1 mts
Last Answer : e. 60.1 mts
Description : The tension T2 will be a.60 N b.5 N c.107 dynes d.15 N e.30 N
Last Answer : e. 30 N
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 : At a roller support the line of reaction and the roller base must be at an angle of a.60? b.90? c.not less than 60? d.not more than 60? e.107 dynes
Last Answer : b. 90?
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 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 grinding wheel rotates at 3000 rpm. When power supply is cut-off the wheel stops in 10 seconds. The number of revolutions made by the wheel before coming to rest would be a.1500 b.3000 c.1000 d.250 e.500
Last Answer : d. 250
Description : According to principle of transmissiblity of forces, when a force acts upon a body, its effect is a.maximum when it acts at C.G. of the body b.minimum when it acts at C.G. of the body c.different at different points of the body d.107 dynes e.same at every point in its line of action
Last Answer : e. same at every point in its line of action
Description : A particle in SHM while passing through mean position will have a.maximum kinetic energy and maximum potential energy b.107 dynes c.maximum kinetic energy and minimum potential energy d.average kinetic energy and average potential energy. e.minimum kinetic energy and maximum potential energy
Last Answer : c. maximum kinetic energy and minimum potential energy
Description : Rain drops (assumed to be spherical) of radii R1, 2R1, 3R, 4R, a.all of them will be zero b.all of them will be same c.drops of radius R will be maximum d.drops of radius R will be minimum e.107 dynes
Last Answer : d. drops of radius R will be minimum
Description : The ideal angle of banking provided on roads a.Depends on (velocity)2 of vehicle b.Depends on the nature of road surface c.Depend on coefficient of friction between the road and the vehicle cantact point d.Depends on weight of the vehicle e.All above
Last Answer : a. Depends on (velocity)2 of vehicle
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 : The common acceleration will be a.1.5 m/s2 b.1.0 m/s2 c.107 dynes d.6 m/s2 e.3 m/s2
Last Answer : b. 1.0 m/s2