03 August, 2016

A planet of mass m moves in the inverse square central force field of the Sun of mass M . If the semi-major and semi-minor axes of the orbit are a and b , respectively, the total energy of the planet is:

          (a)    - ( G M m ) / ( a + b )
          (b)   - ( G M m ) [ ( 1 / a ) + ( 1 / b ) ]
          (c)    – [ ( G M m ) / a ] [ ( 1 / b ) - ( 1 / a ) ]
          (d)   - ( G M m ) / [ ( a – b ) / ( a + b )2 ]

12 June, 2016

जल है तो कल हैं

' एकूण ऋतू किती ? ' असा प्रश्न तुम्हाला विचारलात तर तुम्ही म्हणाल 'सोप्पंय !  तीन ऋतू आहेत , हिवाळा,  उन्हाळा आणि पावसाळा…… '  हे झाले पुस्तकी उत्तर, पण गेल्या चार ते पाच वर्षात झालेल्या वातावरणातील बदल पहिला तर आपल्या लक्षात येईल कि हे  ऋतूचक्रही बदलत चालले आहे.
                     

10 June, 2016

Prove that the angle between the surface of an inclined plane and a the horizontal (the angle of inclination) is equal to the angle between the normal of the plane and the vertical.

Prove that the angle between the surface of an inclined plane and a the horizontal (the angle of inclination) is equal to the angle between the normal of the plane and the vertical.


The angle between the surface of an inclined plane and a the horizontal (the angle of inclination) is equal to the angle between the normal of the plane and the vertical.

08 May, 2016

Two charges of equal magnitude q are placed in air at a distance 2 a apart and third charge -2q is placed at mid – point. The potential energy of a system is? ( ԑo = permittivity of free space ) . (MHT-CET ~ 2014)

Two charges of equal magnitude q are placed in air at a distance 2 a apart and third charge -2q is placed at mid – point. The potential energy of a system is? ( ԑo = permittivity of free space ) . (MHT-CET ~ 2014)

a ] - q 2 / ( 8 π ε o a )                        b] - 3 q 2 / ( 8 π ε o a )                     
c] – 5 q 2 / ( 8 π ε o a )                     d] - 7 q 2 / ( 8 π ε o a )

01 May, 2016

Two concentric sphere kept in air have radii R & r . they have similar change and equal charge density σ. The electric potential at their common centre is? ( MHT - CET ~ 2014 )

Two concentric sphere kept in air have radii R & r . they have similar change and equal charge density σ. The electric potential at their common centre is? ( MHT - CET ~ 2014 )
a ]  σ ( R + r ) / ε o            b ] σ ( R – r ) / ε o
c ] σ ( R + r ) / 2 ε o               d ] σ ( R + r ) / 4 ε o