How will you show that `(17xx11xx2)+(17xx11xx5)` is a composite number? Explain.

Is 7 xx 5 xx 3 xx 2 + 3 a composite number? Justify your answer.

Explain why 7xx11 xx 13 + 13 and 7 xx 6xx 5 xx 4 xx 3 xx 2xx 1 +5 are composite numbers.

The radius of hydrogen atom in its ground state is 5.3xx10^(-11) m. After collision with an electron it is found to have a radius 21.2xx10^(-11) m, then principle quantum number n of the final state of the atom ......

A copper wire is held at the two ends by rigid supports. At 30^(@)C , the wire is just taut, with negligible tension. Find the speed of transverse waves in this wire at 10^(@)C . Given : Young modulus of copper = 1.3 xx 10^(11) N//m^(2) . Coefficient of linear expansion of copper = 1.7 xx 10^(-5) .^(@)C^(-1) . Density of copper = 9 xx 10^(3) kg //m^(3) .

Let A={1,2}, B={1,2,3,4}, C={5,6} and D={5,6,7,8}. Verify that (i) A xx (B cap C)=(A xx B) cap (A xx C), (ii) A xx C is a subset of B xx D

The mean radius of the earth's orbit round the sun is 1.5xx10^(11) . The mean radius of the orbit of mercury round the sun is 6xx10^(10)m . The mercury will rotate around the sun in

The radius of the innermost electron orbit of a hydrogen atom is 5.3 xx 10^(–11) m . What are the radii of the n = 2 and n =3 orbits?