PART - 1 CH - 2 Motion in a Straight Line — Physics STD 11 Science — Question

Should the centre of mass of a body necessarily lie inside the body? Explain.

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?

Give the magnitude and direction of the net force acting on.
A high-speed electron in space far from all material objects, and free of electric and magnetic fields.

The coefficient of performance of a refrigerator depends on which factor?

The coercive force for a certain permanent magnet is 4.0 × 10⁴A/m. Thia magnet is placed inside a long solenoid of 40 turns/cm and a current is passed in the solenoid to demagnetise it completely. Find the current.

A bus weighing 1000kg is at rest on the bus stand. What is the linear momentum of the bus?

Two boys on ice skates hold a rope between them. One boy is much heavier than the other. Discuss their motion when one of the boys pulls on the rope.

Two light sources of intensities 8cd and 12cd are placed on the same side of a photometer screen at a distance of 40cm from it. Where should a 80cd source be placed to balance the illuminance?

What does temperature of a gas express?

NaCl molecule is bound due to the electric force between the sodium and the chlorine ions when one electron. of sodium is transferred to chlorine. Taking the separation between the ions to be 2.75 × 10cm, find the force of attraction between them· State the assumptions (if any) that you have made.