Systems of Particles and Rotational Motion — Physics STD 11 Science — Question

Give the magnitude and direction of the net force acting on.
A kite skillfully held stationary in the sky.

Does the nature of forces differ in solids and liquids? If yes, what is the difference there?

Light is incident normally on a small plane surface. If the surface is rotated by an angle of 30° about the incident light, does the illuminance of the surface increase, decrease or remain same? Does your answer change if the light did not fall normally on the surface? 

Answer the following questions based on the P-T phase diagram of carbon dioxide

1. At what temperature and pressure can the solid, liquid and vapour phases of CO₂ co-exist in equilibrium ?
2. What is the effect of decrease of pressure on the fusion and boiling point of CO₂?
3. What are the critical temperature and pressure for CO₂? What is their significance?
4. Is CO₂ solid, liquid or gas at (a) –70 °C under 1 atm, (b) –60 °C under 10 atm, 15 °C under 56 atm?

Can a tug of war be ever won on a frictionless surface?

Answer the following:
The absolute temperature (Kelvin scale) T is related to the temperature tc on the Celsius scale by tc = T – 273.15.

A man raises a mass m to a height 'h' and then shifts it horizontally by a length x'. What is the work done against the force of gravity?

Pressure is defined as:

1. Momentum per unit area.
2. Momentum per unit area per unit time.
3. Momentum per unit volume.
4. Energy per unit volume.

Minimum velocity of body at lowest point looping in vertical circle of radius r is ________.