Q. N₂ is absorbed in 20% of the surface sites. N₂ gas evolved on heating was collected at 0.001atm and 298 K in a container of volume 2.46cm³. Find out the no. of surface sites occupied per molecule of N_2. If the density of surface sites is 6.023 x 10¹⁴ / cm² and surface area is 1000 cm².

[IIT 2005]

[NOTE : Please the one who wants to post answer to this question can give me the steps of calculation so that it would be clear for me to understand.]

– This is a numeric response type question

Three identical balls are placed on a frictionless horizontal surface touching each other. They stick to each other because of adhesive. Another ball of same radius and mass m is placed over the void created by the three balls. Find the forces applied by the balls kept on the floor to each other if the system remains in equilibrium.

A car loaded with water having total mass 1000 kg moves on a straight horizontal Road starting from rest under the action of a force of 100 Newton. The water spills throw a small hole in the bottom at a rate of 0.1 KG per second the velocity of cart after 300 seconds is nearly.

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