Anish made 42 runs in 6 overs and Anup made 63 runs in 7 overs. Who made more runs per over ?

Some articles made of silver, copper and iron get coloured coating over them when they are exposed to air . Identify the colour and chemical name of the substance of coating in each case.

A right angled triangle of which the sides containing the right angle are 6.3 cm and 10 cm in length, is made to trun around on the longer side. Find the volume of the solid thus generated .

A motor boat heads upstream a distance of 24 km in a river whose current is running at 3 km per hour. The trip up and back takes 6 hours. Assuming that the motor boat maintained a constant speed, what was its speed in still water?

A Si specimen is made into p -type semiconductor by doping on an average one indium atom per 6 xx 10^7 silicon atoms. If the number density of atoms in Si be 6 xx 10^28//m^3 , the indium atoms per cm^3 are

Atwood machine Atwood used the system to prove Netwons laws of motion. Atowood machine consists of two loads of mases m _(1) and m _(2) attached to the ends of a limp of inextensible string as shown in tghe figure 11. The string runs over a pully. FInd the acceleration of each load and tension in the string (m _(1) gt m _(2))