Identify the non-biodegradable wastes from the following:
[I.] Thermal power plants which produce fly ash
[II.] Wastes generated by cotton mills
[III.] Wastes produced by food processing units
[IV.] Slag produced from blast furnace
Identify the correctly matched sets:
CO - neutral oxide GeO - acidic oxide PbO - basic oxide
A block of certain mass is placed on a rough floor. The coefficients of static and kinetic friction between the block and the floor are 0.4 and 0.25 respectively. A constant horizontal force \( F = 20 \, \text{N} \) acts on it so that the velocity of the block varies with time according to the following graph. The mass of the block is nearly (Take \( g = 10 \, \text{m/s}^2 \)):
A wooden block of mass M lies on a rough floor. Another wooden block of the same mass is hanging from the point O through strings as shown in the figure. To achieve equilibrium, the coefficient of static friction between the block on the floor and the floor itself is
Group 15 elements are also known as nitrogen group elements or nitrogen family.
It consists of:
They are present on the right side of the periodic table. All the elements are arranged based on their atomic weight. The elements with similar properties reside in a column called the group.
All Group 15 elements have the electron configuration ns2np3 in their outer shell, where n is the principal quantum number.