A diffraction greating has 5000 lines per cm. what is its greating element?

A long solenoid has 200 turns per cm and carries a current i. The magnetic field at its centre is 6.28xx10^(-2)Wb//m^(2) . Another long solenoid has 100 turns per cm and it carries a current i/3. The value of the magnetic fieldat its centre is

The diagonals of a rhombus are 15 cm and 20 cm.What is its area?

Light of wavelength 5.4 xx 10^(-5)cm passes through a silt 0.12 cm wide and forms a diffraction pattern on a screen 2.7 m away. What is the width of the central maxima?

The diameter of a right circular cone is 4 cm and its volume is 48pi cm^3 . What is its height ?

The atom of an element X has 7 electrons in its M shell. What is the atomic number of element X ?

If a line has direction ratios , then what are its direction cosines?

If a line has direction ratios , then what are its direction cosines?

An element has 2 electrons in the M shell. What is the atomic number of the element ?