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Atoms

Explain Bohr’s postulates for the hydrogen atom. How did these postulates explain the stability of an atom?

Coordinate Geometry

In which quadrant or on which axis each of the following points lie?

(– 3, 5), (4, – 1), (2, 0), (2, 2), (– 3, – 6)

Class 6 – English ( Poorvi )

Can practising Class 6 English Important Questions improve time management?

Dual Nature of Radiation and Matter

Describe the concept of de Broglie wavelength. Calculate the de Broglie wavelength of an electron moving with a given velocity.

From trade to territory

State whether true or false:
(a) The Mughal empire became stronger in the
eighteenth century.
(b) The English East India Company was the only
European company that traded with India.
(c) Maharaja Ranjit Singh was the ruler of Punjab.
(d) The British did not introduce administrative
changes in the territories they conquered.

Wave Optics

Explain the phenomenon of diffraction of light. How does the diffraction pattern change when the wavelength of light is increased?

Coordinate Geometry

Without plotting the points indicate the quadrant in which they will lie, if
(i) ordinate is 5 and abscissa is – 3
(ii) abscissa is – 5 and ordinate is – 3
(iii) abscissa is – 5 and ordinate is 3
(iv) ordinate is 5 and abscissa is 3

Ray Optics

Derive the mirror formula for a concave mirror. Explain the sign conventions used in this derivation.

From trade to territory

Fill in the blanks:
(a) The British conquest of Bengal began with the
Battle of ___________.
(b) Haidar Ali and Tipu Sultan were the rulers of
___________.
(c) Dalhousie implemented the Doctrine of
___________.
(d) Maratha kingdoms were located mainly in the
___________ part of India.

Coordinate Geometry

Plot the following points and check whether they are collinear or not :
(i) (1, 3), (– 1, – 1), (– 2, – 3)
(ii) (1, 1), (2, – 3), (– 1, – 2)
(iii) (0, 0), (2, 2), (5, 5)