Here molecules of gas remains constant. If more pressure is applied to the piston, gaseous molecules will come closer to each other. Hence their volume decreases and density increases. Hope this helps you.
Mgraphs are proportional ofrelationships
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1. Move Towards Renewable Resources.
2. Buy Energy-Efficient Products.
Explanation:
Given that,
Electric field, E = 7900 V/m
Magnetic field, 
(a) Let v is the velocity of a beam of electrons that goes undeflected when moving perpendicular to an electric and magnetic fields. The magnitude of electric force and the magnetic force balance each other as :




(b) Let r is the radius of the electron orbit. The radius of the motion of electron is given by :



Hence, this is the required solution.