Question

Pumping air into a tire increases the pressure inside because ...

... the volume of air inside the tire is increased, hence air molecules have a greater surface area of tire that they hit, increasing the force on the inside wall of the tire.

more air molecules collide with the inside wall of the tire during any given time interval. ...

the higher air density in the tire increases the temperature, which is proportional to pressure in this scenario.

Answer 1

The first assumption is that gases consist of large numbers of tiny particles that are far apart relative to their size. A second assumption is that there are no forces of attraction between gas particles. Gas particles are in continuous, rapid, random motion. The temperature of gas depends on the average kinetic energy of the particles of the gas. Collision between particles of matter are perfectly elastic.

Adding air increases the number of gas particles in the tire. Collision of particles with the inside walls of the tire cause the pressure that is exerted by the enclosed gas. Because of this increasing, the number of air particles increases the number of collisions which then increase the pressure of tire.

When you pump air into a tire, the air particles move about and hit the wall of tire. As you pokumo more air into the tire, more air particles hit the wall of the tire. Thus the pressure increases in the tire because when the air particles hit the wall of the tire, they exert a force on the wall.

The air had nowhere to go as you add more and more air, hence the pressure goes up. Further pumping result in higher and higher pressure and increase in temperature, resulting the breaking of the tire or if it could escape through a hole, the tire might remain the same as you pumped more air in.