Description : For perfectly elastic bodies, the value of the coefficient of restitution is a.1 b.0.372 c.0.5 d.Zero e.Any value between 0 and 1
Last Answer : a. 1
Description : A ball A of mass 0.25 kg moving on a smooth horizontal table with a velocity of 10 m/s strikes an identical stationary ball B on the table. If the impact is perfectly elastic, the velocity of the ball B just after the impact will be a.2.5 m/s b.zero c.5 m/s d.10 m/s e.107 dynes
Last Answer : c. 5 m/s
Description : In the impact problems the following conditions must always be satisfied a.The total kinetic energy remains unchanged b.The total linear momentum remains unchanged c.The magnitude of the total linear ... is reduced by a factor proportional to the coefficient of restitution e.None of the above
Last Answer : b. The total linear momentum remains unchanged
Description : Define coefficient of restitution and obtain its value for an elastic collision and a perfectly inelastic collision.
Last Answer : Define coefficient of restitution and obtain its value for an elastic collision and a perfectly inelastic collision.
Description : A 5 m ladder of mass 25 kg is placed in a position where its inclination to a vertical wall is at 30?. A 100 kg man is to climb the ladder. If the coefficient of static friction is 0.25 the height along ladder at which the slipping will be induced would be a.2.4 m b.1.6 m c.0.8 m d.1.2 m e.0.5 m
Last Answer : c. 0.8 m
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 : 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 crate weighing 40 kg rests on a cart moving with an acceleration W. The coefficient of friction between the cart and the crate is a.2.45 m/sec2 b.4.00 m/sec2 c.0.25 m/sec2 d.4.16 m/sec2 e.1.25 m/sec2
Last Answer : a. 2.45 m/sec2
Description : A ball is allowed to fall freely from a height of 3 metres on to a fixed plate. If the successive rebound heights are h1, h2, h3 a.5 metres b.4.25 metre c.0.5 metre d.1 metre e.Zero
Last Answer : a. 5 metres
Description : The coefficient of static friction will have the highest value in case of a.Mild steel and mild steel b.Mild steel and copper c.Cast iron and steel d.Rope and wood e.Any of the above loctions
Last Answer : d. Rope and wood
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 : 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 : 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 : A weight of 4.9 N rests on a rough horizontal floor that has a coefficient of friction of 0.5. If g = 9.8 m/s2, the smallest horizontal force that gives the weight an acceleration of 4m/s2 is most nearly a.2.5 N b.3 N c.2 N d.4.5 N e.4.9 N
Last Answer : d. 4.5 N
Description : A man wished to move a block of size 3 m x 3 m weighing 80 kg. The coefficient of friction between the block and the ground is 0.27. Which of the following methods should be used? a.Slide along the ground by pushing b.Ask for cranes c.Pull it d.Tip it over e.Lift it bodily
Last Answer : d. Tip it over
Description : In a torsion pendulum a.The body attached to the lower end of wire or rod must be elastic b.The clamp must be elastic c.The clamp must be elastic d.(A) and (B) above e.(A), (B) and (C) together
Last Answer : c. The clamp must be elastic
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. ... c.Indeterminate d.Determinate but depends on the acceleration of the cylinder e.None of the above
Last Answer : c. Indeterminate
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 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 : Which of the following bearing will have least coefficient of friction a.Single ball bearing b.Cylinderical roller bearing c.Self aligury bearing d.Thrust ball bearing e.Tapered bearing
Last Answer : e. Tapered bearing
Description : The coefficient of friction is a.The tangent of the angle between the normal reaction and direction of limiting friction b.The tangent of the angle between the normal reaction and the resultant ... e.The angle between the normal reaction and the resultant of normal reaction and the limiting friction
Last Answer : a. The tangent of the angle between the normal reaction and direction of limiting friction
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 : The moment of a force a.Occurs about a point b.Measures the capacity to do useful work c.Occurs only when bodies are in motion d.Measures the ability to produce turning or twisting about an axes e.None of the above
Last Answer : d. Measures the ability to produce turning or twisting about an axes
Description : Coulomb friction is a.Friction between solids and liquids b.Friction between electrically charged bodies c.Friction between lubricated surface d.Friction between dry surfaces e.Friction between bodies having relative motion
Last Answer : d. Friction between dry surfaces
Description : If two bodies one light and one heavy have equal kinetic energies, which one has a greater momentum? a.Momentum depends on velocities b.Heavy body c.Both have equal momentum d.Nothing can be concluded on the basis of information provided e.Light body
Last Answer : b. Heavy body
Description : Plastic collosion of two bodies of equal mass results in a common velocity after impact which is a.Sum of their initial velocities b.Difference of their initial velocities c.Average of their initial velocities d.Independent of their initial velocities e.None of the above
Last Answer : e. None of the above
Description : Which of the following statement is false? a.The potential energy of a particle has the form Ep = k2x. The force acting on the particle is constant (k is a constant) b.The linear velocity of ... zag path while ascending a steep hill e.The density of milk decreases when cream is taken out of milk
Last Answer : e. The density of milk decreases when cream is taken out of milk
Description : Which one of the following is not the law of dry friction? a.If friction is neglected, the reactions are always normal to the surfaces on contact b.Friction always acts to oppose the relative motion of ... its maximum value d.The force of friction is always normal to the surface e.All of the above
Last Answer : d. The force of friction is always normal to the surface
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 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 : A force F = 2i + 3j - k is passing through the origin. Its moment about point (1, 1, 0) is a.Zero b.2i + 3j c.i - j - k d.i + j e.i + j + k
Last Answer : c. i - j - k
Description : A force F = 2i + 3j - k is passing through the origin. Its moment about point (1, 1, 0) is a.107 dynes b.i + j + k c.2i + 3j d.zero e.i - j - k
Last Answer : b. i + j + k
Description : M.I. of sphere of 0.5 m radius about a mutually perpendicular axis (Z-axis) when its M.I. about X-axis and Y-axis are 50 kgm2 and 50 kgm2 is a.50 Kgm2 b.Tapered bearing c.100 Kgm2 d.25 Kgm2 e.12.5 Kgm2
Last Answer : a. 50 Kgm2
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 : If four turms of rope around a horizontal post will hold a 100 kg weight with a pull of 1 kg, then a.107 dynes b.0.25 c.0.18 d.0.3 e.0.11
Last Answer : c. 0.18
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 : 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 : The law of conservation of mechanical energy is valid a.Irrespective of the nature of force field b.Only in gravitational field c.Only if the total work done by the particle in moving around in a closed trajectory is zero d.Only if the force is tangential to the trajectory e.None of the above
Last Answer : c. Only if the total work done by the particle in moving around in a closed trajectory is zero
Description : A stone weighing 20 N is whirling in a vertical circle at the extremity of a string 100 cm long. The tension in the string will be zero a.at the highest position b.at the lowest position c.at the midway position d.at none of the above e.107 dynes
Last Answer : a. at the highest position
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 : If the angle of friction is zero a body will experience a.Infinite friction b.Zero friction c.The force of friction will act normal to the plane d.The force of friction will act in the direction of motion e.None of the above
Last Answer : b. Zero friction
Description : A body of weight W is resting at a plane inclined at 30? to the horizontal. It is attached to a string making an angle of 60? with horizontal. If the angle of friction be 30? the tension in the string would be a.Zero b.W c.W/2 d.2W e.None of the above
Last Answer : c. W/2
Description : A number of forces acting at a point will be in equilibrium if a.Sum of the forces is zero b.Algebraic sum of the forces is zero c.Sum of the resolved parts in any two perpendicular directions are both zero d.None of the above e.The metacentre of the body
Last Answer : d. None of the above
Description : If air resistance is neglected, at the mid-point of its swing, the acceleration of the bob of a simple pendulum along its path is always a.Increasing b.Zero c.A cycloid d.Decreasing e.A minimum but not equal to zero
Last Answer : d. Decreasing
Description : Under which circumstances will have zero velocity and be still accelerating? a.The bob of a simple pendulum when at its mean position b.107 dynes c.A steamer while taking a turn d.A ball at its highest point of its rise when thrown up e.Tyres of a stationary automobile
Last Answer : d. A ball at its highest point of its rise when thrown up
Description : When two concurrent and coplaner forces P and Q act at an angle of 180?, their resultant will be a a.moment equal to PQ b.couple c.(P-Q) d.107 dynes e.zero
Last Answer : c. (P-Q)
Description : A beam fixed at both ends with a central load W in the middle will have zero bending moment at a.one place b.two places c.no where d.three places e.107 dynes
Last Answer : b. two places
Description : Our weight will be zero under all of the following conditions EXCEPT a.107 dynes b.We are at the centre of the earth c.When we are ascending in a lift with acceleration of 4.9 m/s2 d.We are orbiting in a satellite e.When we are freely faling
Last Answer : c. When we are ascending in a lift with acceleration of 4.9 m/s2
Description : The torque acting on a system is zero. Which of the following will be conserved? a.Angular velocity b.Linear momentum c.107 dynes d.Angular momentum e.Moment of inertia
Last Answer : d. Angular momentum
Description : The necessary condition of equilibrium of a body is a.The algebraic sum of horizontal components of all forces must be zero b.The algebraic sum of vertical components of all forces must be zero c.The algebraic sum of forces about a point must be zero d.All the above e.None of the above
Last Answer : d. All the above