It is postulated that the collisons between gas moelcule are elastic? What would have happened had the collisions not been elastic?

A railway carriage of mass 9,000 kg moving with a speed of 36 km h^-1 strikes a stationary carriage of same mass. After the collision, the carriages get coupled and move together. what is their common speed after collision? Is the collision elastic?

When two identical spheres collide obliquely with one of them initialyly at rest,then fly off making an angle theta .What is the value of angle theta if the collision is elastic?

If the distance between two equal points charges is doubled and their individual charges are also doubled, what would happen to the force between them?

What is coefficient of restitution? What is its value for perfectly elastic and inelastic collisions?

A molecule in a gas container hits a horizontal wall with speed 200 m s_1 and angle 30^@ with the normal, and rebounds with the same speed. Is momentum conserved in the collision ? Is the collision elastic or inelastic ?

Answer carefully, with reasons: If the potential energy of two billiard balls depends only on the separation distance between their centres, is the collision elastic or inelastic?

A cricket ball of mass 150 g moving with a speed of 126 km/h hits at the iddle of the bat, held firmly at its position by the batsman. The ball moves straight back to the bowler after hitting the bat. Assurming that collision between ball and bat is completely elastic and the two remain in contact for 0.001 s, the force that the batsman had to apply to hold the bat firmly at its place would be

Long Answer Questions Five mark Each QUESTIONS FROM CBSE BOARD EXAMINATIONS : A flower of tomato plant following the process of sexual reproduction produces 240 viable seeds. Answer the following questions giving reasons: (a) What is the minimum number of pollen grains that must have been involved in the pollination of its pistil? (b) What would have been the minimum number of ovules present in the ovary? (c) How many megaspore mother cells were involved? (d) What is the minimum number of microspore mother cells involved in the above case? (e) How many male gametes were involved in this case?