Skip to main content

भारतीय रसायन के पिता आचार्य प्रफुल्ल चंद्र रे की जयंती पर व्याख्यान का आयोजन

भारतीय रसायन के पिता आचार्य प्रफुल्ल चंद्र रे की जयंती पर व्याख्यान का आयोजन विज्ञान भारती उदयपुर इकाई एवं बीएन कॉलेज ऑफ फार्मेसी, बीएन विश्वविद्यालय के संयुक्त तत्वावधान में कार्यक्रम सम्पन्न उदयपुर, 2 अगस्त। भारतीय रसायन के पिता आचार्य प्रफुल्ल चंद्र रे की जयंती के अवसर पर विज्ञान भारती उदयपुर इकाई (चित्तौड़ प्रांत) एवं बीएन कॉलेज ऑफ फार्मेसी, बीएन विश्वविद्यालय के संयुक्त तत्वावधान में एक विशेष व्याख्यान का आयोजन किया गया। कार्यक्रम का उद्देश्य आचार्य पी.सी. रे के वैज्ञानिक योगदान एवं उनके देशभक्ति से ओतप्रोत जीवन पर प्रकाश डालना था। ज्ञातव्य है कि भारत की पहली फार्मा कंपनी आचार्य रे ने ही बंगाल केमिकल एंड फार्मास्यूटिकल्स लिमिटेड, कोलकाता में 1901 में प्रारंभ की थी। कार्यक्रम में विज्ञान भारती के उद्देश्य एवं गतिविधियों की जानकारी डॉ. अमित गुप्ता द्वारा दी गई। आचार्य पी.सी. रे के जीवन और कार्यों पर मुख्य व्याख्यान डॉ. लोकेश अग्रवाल द्वारा प्रस्तुत किया गया। उन्होंने बताया कि कैसे आचार्य रे ने विज्ञान को समाज की सेवा का माध्यम बनाया और रसायन विज्ञान में भारत को आत्मनिर्भर बनान...

Abbe’s sine condition | Optics

Abbe’s sine condition

Sign convention

For axial or longitudinal distance

  • The distances measured along optic axis or parallel to optic axis are known as axial or longitudinal distance.
  • All the distances measured in the direction of incident ray from optical centre O are taken as positive, and all the distances measured in the direction opposite to the incident ray are taken as negative.

For transverse or lateral distance

  • All the distances measured perpendicular to the optic axis are known as transverse or lateral distances.
  • The transverse distances above the optic axis are taken as positive and the transverse distances below the optic axis are taken as negative.

For angles

  • The angles measured in anticlockwise direction with optic axis are measured as positive, and the angles measured in clockwise directions are measured as negative.
  • ∠ θ1 is negative, and ∠θ2 is positive.

            Note

    • All the longitudinal distances should be measured from optical centre, and all the lateral distances should be measured from optic axis.


      Abbe’s sine condition

    • By using sign convention
    • h1 and v are positive.
    • h2 and u are negative
    • θ1 and i are positive, and θ2 is negative.
    • From △CNM and △CN՛M
    ՛
    • By using sine law in △ANC

    • By using sine law in △AN՛C
    • This is Abbe's since condition.
    • This relation is valid for all the values of θ1 and θ2.
    • In this way a point N on axis imaged as N՛ on the axis by refraction from the surface XY.
    • A surface which does so, is known as aplantic surface, and this surface is used in objectives of microscopes.
    • If aperture of the refracting surface is very small, then θ1 and θ2 will be very small.
    • ∴   sin θ1 ≈ tan θ1 and sin θ2 ≈ tan θ2
    • µ1h1 tan θ1 = µ2h2 tan θ2
    • This is Lagrange’s equation.
    • Also if the values of θ1 and θ2 are very small, then tan θ1 ≈ θ1 and tan θ2 ≈ θ2
    • µ1h1 θ1 = µ2h2 θ2
    • This is Helmholtz equation.

    Comments

    Popular posts from this blog

    Aplanatic points of a spherical refracting surface | Optics | General theory of image formation

    Aplanatic points of a spherical refracting surface From Abbe’s sine condition                                  If this ratio is constant for a particular surface, then the surface is known as aplanatic surface . An aplanatic surface is a surface which forms a point image of a point object situated on its axis. The image formed by aplanatic surface is free from optical aberrations. Using sine law in △OPC                                                                            ...(1) Since refraction is taking place from denser to rarer, so from Snell's law              ...

    Advantage and Disadvantage of Power Electronics

    Advantage and Disadvantage of Power Electronics Advantage of Power electronics Power electronics is used in space shuttle power supplies Since there is very low loss in power electronic devices so its efficiency is very high. Power electronic converter systems are highly reliable. Since there is no moving parts in power electronic systems so it has long life and also its maintenance cost is very less. The power electronic systems has fast dynamic response in comparison to electromechanical converter systems. Since the power electronic system has small size and also it has less weight so they occupy less floor space and hence their installation cost is also less. Now these days power equipments are being mostly used, so power semiconductor devices are being produced on a large scale, resulting in lower cost of converter equipment. Power electronics are used in computer and office equipments. It is used in uninterruptible power supplies. Power...

    Cardinal points of a lens system | Optics | General theory of image formation

    Cardinal points of a lens system There are total six cardinal points of a lens system, which are first and second focal points, first and second principal points, and first and second nodal points. First and second focal points (First and second focal planes) A pair of points lying on the principal axis and conjugate to points at infinity are known as focal points. First and Second focal points A point on the principal axis in the object space so that the rays starting (or appear to start) from it become parallel to the principal axis after refraction from the lens system is known as first focal point (F 1 ). A point on the principal axis in the image space so that the rays parallel to the principal axis in the image space focus (or appear to focus) at this point after refraction from the lens system is known as second focal point (F 2 ). First and Second focal planes The plane passing through the first focal point, and perpendicular to the optic axis is first f...