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

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
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d. Friction between dry surfaces
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Coulomb friction is the friction between (A) Bodies having relative motion (B) Two dry surfaces (C) Two lubricated surfaces (D) Solids and liquids

Description : Coulomb friction is the friction between  (A) Bodies having relative motion  (B) Two dry surfaces  (C) Two lubricated surfaces  (D) Solids and liquids 

Last Answer : (A) Bodies having relative motion 

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 the free body c.If static friction is acting, the value of the friction force may vary from zero to its maximum value d.The force of friction is always normal to the surface e.All of the above

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

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

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

Which of the following statements is/are true for coulomb damping? 1. Coulomb damping occurs due to friction between two lubricated surfaces2. Damping force is opposite to the direction of motion of vibrating body 3. For smooth surfaces, coefficient of friction depends upon velocity 4. Damping force depends upon the rubbing velocity between two rubbing surfaces a. Only statement 1 b. Statement 2, 3 and statement 4 c. Only statement 2 d. All the above statements are true

Description : Which of the following statements is/are true for coulomb damping? 1. Coulomb damping occurs due to friction between two lubricated surfaces2. Damping force is opposite to the direction of motion of vibrating body ... 2, 3 and statement 4 c. Only statement 2 d. All the above statements are true

Last Answer : c. Only statement 2

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

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

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

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

A body of weight 100 kg is placed on a horizontal plane. A horizontal force of 30 kg is applied and the block is just on the point of motion. The angle of friction is a.About 16? b.30? c.45? d.60? e.None of the above

Description : A body of weight 100 kg is placed on a horizontal plane. A horizontal force of 30 kg is applied and the block is just on the point of motion. The angle of friction is a.About 16? b.30? c.45? d.60? e.None of the above

Last Answer : a. About 16?

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 of the normal reaction and the limiting friction c.The tangent of the angle of the net resultant force with the direction of motion d.The tangent of the angle between the horizontal plane and the resultant force e.The angle between the normal reaction and the resultant of normal reaction and the limiting friction

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

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 cannot exceed under a situation d.The friction force acting when the body is just about to move e.Double of the normal friction

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

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.Proportional to the coefficient of static friction b.Proportional to the coefficient of dynamic friction c.Indeterminate d.Determinate but depends on the acceleration of the cylinder e.None of the above

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

Ice is slippery when a man walks on it because a.Increase of pressure causes it to melt b.Ice is brittle c.There is no friction d.It is very chill e.Its surface is smooth

Description : Ice is slippery when a man walks on it because a.Increase of pressure causes it to melt b.Ice is brittle c.There is no friction d.It is very chill e.Its surface is smooth

Last Answer : a. Increase of pressure causes it to melt

The angle which an inclined surface makes with the horizontal when a body placed on it is on the point moving down is known as a.Angle of friction b.Angle of limiting friction c.Angle of inclination d.Angle of repose e.None of the above

Description : The angle which an inclined surface makes with the horizontal when a body placed on it is on the point moving down is known as a.Angle of friction b.Angle of limiting friction c.Angle of inclination d.Angle of repose e.None of the above

Last Answer : d. Angle of repose

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

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

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.Indeterminate b.Proportional to the coefficient of dynamic friction c.Determinate but depends on the acceleration of the cylinder d.107 dynes e.Proportional to the coefficient of static friction

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

The maximum frictional force which comes into play when a body just begins to slide over the surface of another body is known as a.Kinetic friction b.Rolling friction c.Dynamic friction d.Limiting friction e.Sliding friction

Description : The maximum frictional force which comes into play when a body just begins to slide over the surface of another body is known as a.Kinetic friction b.Rolling friction c.Dynamic friction d.Limiting friction e.Sliding friction

Last Answer : d. Limiting friction

The maximum efficiency of a scres jack having square threads and friction angle of 30 degree will be a.0.2 b.0.11 c.0.05 d.0.33 e.0.09

Description : The maximum efficiency of a scres jack having square threads and friction angle of 30 degree will be a.0.2 b.0.11 c.0.05 d.0.33 e.0.09

Last Answer : d. 0.33

Which of the following statement is incorrect? a.A body can have energy without having momentum b.A body cannot have kinetic energy without having momentum c.A body in motion will always have kinetic energy more than the potential energy d.None of the above e.107 dynes

Description : Which of the following statement is incorrect? a.A body can have energy without having momentum b.A body cannot have kinetic energy without having momentum c.A body in motion will always have kinetic energy more than the potential energy d.None of the above e.107 dynes

Last Answer : c. A body in motion will always have kinetic energy more than the potential energy

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

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

For perfectly elastic bodies the value of the coefficient of restitution is a.0.707 b.0.5 c.1 d.0.25 e.Zero

Description : For perfectly elastic bodies the value of the coefficient of restitution is a.0.707 b.0.5 c.1 d.0.25 e.Zero

Last Answer : a. 0.707

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 bodies b.107 dynes c.inversely proportional to the respective masses of the bodies d.directly proportional to the square of the respective masses of the bodies e.inversely proportional to the square of the respective masses of the bodies

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

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

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

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

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

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 bodies near the earth's equator (due to rotation of earth) is more than the velocities of particles at the pole c.107 dynes d.A cyclist should move along a zig-zag path while ascending a steep hill e.The density of milk decreases when cream is taken out of milk

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

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

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

The slope on the road generally provided on the curves is known as a.Angle of repose b.Angle of friction c.Angle of banking d.Angle of reaction e.None of the above

Description : The slope on the road generally provided on the curves is known as a.Angle of repose b.Angle of friction c.Angle of banking d.Angle of reaction e.None of the above

Last Answer : c. Angle of banking

The angle of friction is a.The angle which frictional force makes with the normal b.The anle at which the force applied from external souce will cause movement c.The angle at which fictional force is inclined to external force d.The angle between the normal reaction and the resultant of normal reaction and the limiting friction e.None of the above

Description : The angle of friction is a.The angle which frictional force makes with the normal b.The anle at which the force applied from external souce will cause movement c.The angle at which fictional ... the normal reaction and the resultant of normal reaction and the limiting friction e.None of the above

Last Answer : d. The angle between the normal reaction and the resultant of normal reaction and the limiting friction

A block of weight 20 kg slides with an initial velocity of 2 m sec down an inclined plane on to a spring of stiffness 10 kg/cm. If the co--efficient of friction is 0.2, angle ? = 30 the ratio of maximum compession of spring, neglecting friction to that while considering friction would be a.More than one b.One c.Less than one d.Depends on the stiffness of spring e.None of the above

Description : A block of weight 20 kg slides with an initial velocity of 2 m sec down an inclined plane on to a spring of stiffness 10 kg/cm. If the co--efficient of friction is 0.2, angle ? = 30 the ratio of ... be a.More than one b.One c.Less than one d.Depends on the stiffness of spring e.None of the above

Last Answer : a. More than one

The principle of conservation of energy cannot be applied in case of a.Flow of heat through a metal b.Ideal flow of water in a pipe c.Simple pendulum d.Sliding of a particle along inclined plane with friction e.A particle moving in gravitational field

Description : The principle of conservation of energy cannot be applied in case of a.Flow of heat through a metal b.Ideal flow of water in a pipe c.Simple pendulum d.Sliding of a particle along inclined plane with friction e.A particle moving in gravitational field

Last Answer : e. A particle moving in gravitational field

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

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

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

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

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

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

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

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

A particle moves along a rough plane inclined at 30? to the horizontal. The co-efficient of friction between the particle and the plane is 0.1. Its initial velocity is 15 m/sec. The ratio of the velocity of the particle when it move down the plane to that when it move up the plane would be in the regions a.8 ? 10 b.5 ? 7 c.2 ? 3 d.4 ? 6 e.10 ? 13

Description : A particle moves along a rough plane inclined at 30? to the horizontal. The co-efficient of friction between the particle and the plane is 0.1. Its initial velocity is 15 m/sec. The ratio of the velocity of the particle when it move ... be in the regions a.8 ? 10 b.5 ? 7 c.2 ? 3 d.4 ? 6 e.10 ? 13

Last Answer : b. 5 ? 7

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

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

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

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

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 force exerted by the jet on the plate would be in the range a.15 - 20 kg b.20 - 25 kg c.5 - 10 kg d.25 - 30 kg e.10 - 15 kg

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

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

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

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

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

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

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

Which of the following is scalar quantity a.Area of triangle b.Displacement of a particle c.Acceleration of car d.Force of friction e.Velocity a gear

Description : Which of the following is scalar quantity a.Area of triangle b.Displacement of a particle c.Acceleration of car d.Force of friction e.Velocity a gear

Last Answer : a. Area of triangle

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

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

Polar moment of inertia is a.Applicable to masses whereas moment of inertia is applicable to area only b.The moment of inertia for an area ralative to a line or axis which is out the plane of area c.Same as moment of inertia d.The moment of inertia for an area relative to a line or axis parallel to the centroidal axis e.The moment of inertia for an area relative to a line or axis perpendicular to the plane of the area

Description : Polar moment of inertia is a.Applicable to masses whereas moment of inertia is applicable to area only b.The moment of inertia for an area ralative to a line or axis which is out the plane of area ... The moment of inertia for an area relative to a line or axis perpendicular to the plane of the area

Last Answer : e. The moment of inertia for an area relative to a line or axis perpendicular to the plane of the area

A block slides down a frictionless incline making an angle ? with an elevator floor. The acceleration relative to the incline will be maximum when a.the elevator ascends at constant speed v b.the elevator descends at constant speed v c.107 dynes d.elevator descends with deceleration a e.the elevator descends with acceleration a

Description : A block slides down a frictionless incline making an angle ? with an elevator floor. The acceleration relative to the incline will be maximum when a.the elevator ascends at constant speed v b. ... speed v c.107 dynes d.elevator descends with deceleration a e.the elevator descends with acceleration a

Last Answer : d. elevator descends with deceleration a

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

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

During planetary motion which of the following remains constant? a.Augular speed b.Linear velocity c.Angular acceleration d.Total angular momentum e.All of the above

Description : During planetary motion which of the following remains constant? a.Augular speed b.Linear velocity c.Angular acceleration d.Total angular momentum e.All of the above

Last Answer : b. Linear velocity

A particle in simple Harmonic Motion while passing through mean position will have a.Maximum kinetic energy and minimum potential energy b.Average kinetic energy and average potential energy c.Minimum kinetic energy and maximum potential energy d.Maximum kinetic energy and maximum e.Minimum kinetic energy and minimum potential energy

Description : A particle in simple Harmonic Motion while passing through mean position will have a.Maximum kinetic energy and minimum potential energy b.Average kinetic energy and average potential energy c. ... energy d.Maximum kinetic energy and maximum e.Minimum kinetic energy and minimum potential energy

Last Answer : a. Maximum kinetic energy and minimum potential energy

The motion of a bicycle wheel is a.Curvilinear b.Translatory c.Linear d.Rotary as well as translatory e.Rotary

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

When a body moves round a fixed axis it will have a.A motion of rotation and translation b.A circular motion c.A rotary motion d.A translatory motion e.A swinging motion

Description : When a body moves round a fixed axis it will have a.A motion of rotation and translation b.A circular motion c.A rotary motion d.A translatory motion e.A swinging motion

Last Answer : b. A circular motion

If for power transmission a gear train consisting of 8 gears is used, then a.the motion of driver and follower will be in the same direction b.the motion of driver and follower will be in the opposite directions c.either of (A) or (B) above d.None of the above e.107 dynes

Description : If for power transmission a gear train consisting of 8 gears is used, then a.the motion of driver and follower will be in the same direction b.the motion of driver and follower will be in the opposite directions c.either of (A) or (B) above d.None of the above e.107 dynes

Last Answer : b. the motion of driver and follower will be in the opposite directions