A shopkeeper sells 5 rings , 8 bracelets and 10 necklaces in first week and 11 rings 6 bracelets and 9 necklaces in next week .Show this information in a `2xx3` matrix .

A steel rod is 3.000 cm in diameter at 25^@C . A brass ring has an interior diameter of 2.992 cm at 25^@C . At what common temperature will the ring just slide onto the rod ? (Coefficient of linear expansion of steel= 12 xx 10^(-6) per k and coefficient of linear expansion of brass= 18 xx 10^(-6) per k) .

The electron in the first orbit of hydrogen atom revolves round the nucleus in a circular orbit of radius 0.5 overset@A with a speed 2.18xx10^(6) m/s . What is the centripetal force acting on the electron ? (Mass of electron = 9.1xx10^(-31) kg).

A thick rope of rubber of density 1.5 (kg)/m^3 Young's modulus 5 xx 10^6 N/M^2 and length 8m is hung from the ceiling of a room . The increase in length due to its own weight is

A copper wire of 2.5 xx 10^-6 m^2 area carries a current of 1.6A. If the number density of the electrons in the wire is 8 xx 10^28//m^3 , then calculate the drift speed of the electrons in the wire (e = 1.6 xx 10^-19 C)