Lithium borohydride `(LiBH_4)` crystallizes in an orthorhombic system having 4 molecules per unit cell. The unit dimesions are: `a=6.81 oversetcircA`, `b=4.43 oversetcircA` and `c=7.17 oversetcircA`. Cacluate the density of the crystal (At. Mass of Li=7, B=11, H=1u).

Sodium metal crystallizes in a body centre cubic lattice with a unit cell edge 4.29 oversetcircA . The radius of sodium atom is approximately

An element (density 7.2 gcm^-3) crystallizes in a body centred cubic structure having its unit cell edge length 2.88oversetcircA . Calculate the number of atoms present in 156 g of the element.

Chromium crystallizes in a body centred cubic lattice whose density is 7.20g/cm^3 . The length of the edge of the unit cell is 288.4 pm. Calculate the Avogadro number (atomic mass of chromium=52).

Silver metal crystallise with a face centred cubic .lattice. The length of unit cell is found to be 4.077 xx 10^(-8) cm . Calculate the atomic radius and density of silver (Atomic mass of Ag= 108 u, NA= 6.02 x 10^(23) mol^(-1) .

A manufacturer produces two products A and B. Both the products are processed on two different machines. The available capacity of first machine is 12 hours and that of second machine is 9 hours per day. Each unit of product A requires 3 hours on both machines and each unit of product B requires 2 hours on first machine and 1 hour on secnd machine. Each unit of product A is sold at Rs 7 profit and that of B at a profit of Rs 4. Find the production level per day for maximum profit graphically.

A manufacturer produces two products A and B. Both the products are processed on two different machines. The available capacity of first machine is 12 hours and that of second machine is 9 hours per day. Each unit of product A requires 3 hours on both machines and each unit of product B requires 2 hours on first machine and 1 hour on second machine. Each unit of product A is sold at ₹ 7 profit and that of B at a profit oft ₹ 4. Find the production level per day for maximum profit graphically.

A current of 2.4 A flows through a wire of cross-sectional area 1.5 mm^2 . Find the current density in the wire. If the wire contains 8 xx 10^28m^-3 elecrtrons per unit volume calculate the average relaxation on time. Given that charge on electron = 1.6 xx 10^-19C and mass of electron =9.1 xx 10^-31 kg.

A triangle A B C with vertices A(-1,0),B(-2,3/4), and C(-3,-7/6) has its orthocentre at Hdot Then, the orthocentre of triangle B C H will be

In an equilateral triangle, three coins of radii 1 unit each are kept so that they touch each other and also the sides of the triangle. The area of the triangle is 2sqrt(3) (b) 6+4sqrt(3) 12+(7sqrt(3))/4 (d) 3+(7sqrt(3))/4