Mechanical Properties of Solids — Physics STD 11 Science — Question

Angle of friction which the resultant of limiting friction and normal reaction makes with the normal, is numerically equal to ______.

What is the effect:

1. Of highly soluble impurities on the surface tension of a liquid?
2. Of less soluble impurities on the surface tension of a liquid?
3. On the angle of contact when the temperature of a liquid is increased?

A body of mass 2kg initially at rest moves under the action of an applied horizontal force of 7N on a table with coefficient of kinetic friction = 0.1. Compute the:
Work done by friction in 10 s.

A string clamped at both ends vibrates in its fundamental mode. Is there any position (except the ends) on the string which can be touched without disturbing the motion? What if the string vibrates in its first overtone?

What are the necessary conditions for a process to be reversible?

A satellite is orbiting around the Earth with a speed v. To make the satellite escape, what is the minimum percentage increase in its speed?

Can two isothermal curves intersect? Why?

If, in Exercise 5.21, the speed of the stone is increased beyond the maximum permissible value, and the string breaks suddenly, which of the following correctly describes the trajectory of the stone after the string breaks:

1. The stone moves radially outwards.
2. The stone flies off tangentially from the instant the string breaks.
3. The stone flies off at an angle with the tangent whose magnitude depends on the speed of the particle?

Are physical quantities having both magnitude and direction always vector quantities?