Physics-
General
Easy
Question
Which is a suitable method to decrease friction :
- Ball and bearings
- Lubrication
- Polishing
- All the above
The correct answer is: All the above
Related Questions to study
physics-
Two masses A and B of 10 kg and 5 kg respectively are connected with a string passing over a frictionless pulley fixed at the corner of a table as shown. The coefficient of static friction of A with table is 0.2. The minimum mass of C that may be placed on A to prevent it from moving is :
Two masses A and B of 10 kg and 5 kg respectively are connected with a string passing over a frictionless pulley fixed at the corner of a table as shown. The coefficient of static friction of A with table is 0.2. The minimum mass of C that may be placed on A to prevent it from moving is :
physics-General
physics-
In the figure shown, a block of weight 10 N resting on a horizontal surface. The coefficient of static friction between the block and the surface µs = 0.4. A force of 3.5 N will keep the block in uniform motion, once it has been set in motion. A horizontal force of 3 N is applied to the block, then the block will :
In the figure shown, a block of weight 10 N resting on a horizontal surface. The coefficient of static friction between the block and the surface µs = 0.4. A force of 3.5 N will keep the block in uniform motion, once it has been set in motion. A horizontal force of 3 N is applied to the block, then the block will :
physics-General
physics-
The coefficient of friction µ and the angle of friction 
are related as :
The coefficient of friction µ and the angle of friction are related as :
physics-General
physics-
Assertion (A) : A charged particle is free to move in an electric field. It does not move along an electric line of force ?
Reason (R) : Its initial position decides that it will move along the line of force or not.
Assertion (A) : A charged particle is free to move in an electric field. It does not move along an electric line of force ?
Reason (R) : Its initial position decides that it will move along the line of force or not.
physics-General
physics-
Assertion (A) : Though large number of free electrons are present in the metal, yet there is no current in the absent of electric field.
Reason (R) : In the absence of electric field, electrons move randomly in all directions.
Assertion (A) : Though large number of free electrons are present in the metal, yet there is no current in the absent of electric field.
Reason (R) : In the absence of electric field, electrons move randomly in all directions.
physics-General
physics-
Charges +q and –q are placed at points A and B respectively which are a distance 2L apart, C is the midpoint between A and B. the work done in moving a charge +Q along the semicircle CRD is:
Charges +q and –q are placed at points A and B respectively which are a distance 2L apart, C is the midpoint between A and B. the work done in moving a charge +Q along the semicircle CRD is:
physics-General
physics-
A hollow cylinder has a charge q coulomb within it. If 
is the electric flux in units of voltmeter associated with the curved surface B, the flux linked with the plane surface A in units of voltmeter will be:
A hollow cylinder has a charge q coulomb within it. If is the electric flux in units of voltmeter associated with the curved surface B, the flux linked with the plane surface A in units of voltmeter will be:
physics-General
physics-
A square surface of side L metres is in the plane of the paper. A uniform electric electric field 
(volt/m), also in the plane of the paper, is limited only to the lower half of the square surface(as shown in figure). The electric flux in SI units associated with the surface is
A square surface of side L metres is in the plane of the paper. A uniform electric electric field (volt/m), also in the plane of the paper, is limited only to the lower half of the square surface(as shown in figure). The electric flux in SI units associated with the surface is
physics-General
physics-
To charges q1 and q2 are placed 30 cm apart, shown in the figure. A third charge q3 is moved along the arc of a circle of radius 40 cm from C to D. The change in the potential energy of the system is 
where k is
To charges q1 and q2 are placed 30 cm apart, shown in the figure. A third charge q3 is moved along the arc of a circle of radius 40 cm from C to D. The change in the potential energy of the system is where k is
physics-General
physics-
As per this diagram a point charge +q is placed at the origin O. Work done in taking another point charge —Q from the point A [co-ordinates (0, a)] to another point B [co-ordinates (a, 0)] along the straight path AB is
As per this diagram a point charge +q is placed at the origin O. Work done in taking another point charge —Q from the point A [co-ordinates (0, a)] to another point B [co-ordinates (a, 0)] along the straight path AB is
physics-General
physics-
Figure shows three points A, B and C in a region of uniform electric field E. The line AB is perpendicular and BC is parallel to the field lines. Then which of the following holds good. Where VA ,VB and VC represent the electric potential at points A, B and C respectively
Figure shows three points A, B and C in a region of uniform electric field E. The line AB is perpendicular and BC is parallel to the field lines. Then which of the following holds good. Where VA ,VB and VC represent the electric potential at points A, B and C respectively
physics-General
physics-
A charge q is located at the centre of a cube. The electric flux through any face is
A charge q is located at the centre of a cube. The electric flux through any face is
physics-General
physics-
Four charges +Q, –Q, + Q, –Q are placed at the corners of a square taken in order. At the centre of the square
Four charges +Q, –Q, + Q, –Q are placed at the corners of a square taken in order. At the centre of the square
physics-General
physics-
A cylinder of radius R and length L is placed in a uniform electric field E parallel to the cylinder axis. The total flux for the surface of the cylinder is given by
A cylinder of radius R and length L is placed in a uniform electric field E parallel to the cylinder axis. The total flux for the surface of the cylinder is given by
physics-General
physics-
A solid conducting sphere of radius a has a net positive charge 2Q. A conducting spherical shell of inner radius b and outer radius c is concentric with the solid sphere and has a net charge –Q. The surface charge density on the inner and outer surfaces of the spherical shell will be
A solid conducting sphere of radius a has a net positive charge 2Q. A conducting spherical shell of inner radius b and outer radius c is concentric with the solid sphere and has a net charge –Q. The surface charge density on the inner and outer surfaces of the spherical shell will be
physics-General
