What causes the pressure in a tire to increase when it is warmed up due to friction?

The increase in pressure within a tire when it warms up due to friction is caused by the behavior of air molecules inside the tire. As the temperature of the tire rises, the kinetic energy of the air molecules also increases. This increased kinetic energy causes the molecules to move faster. As a result, the frequency and force of the collisions between the air molecules and the walls of the tire increase.

According to the principles of the kinetic molecular theory, gas pressure is directly related to the number of collisions between gas molecules and the surfaces of their container. When the air molecules are moving more rapidly, they collide with the walls of the tire more often and with greater force, thereby raising the internal pressure.

The other choices do not accurately describe the effects of temperature on gas pressure. For example, gas escaping from the tire would decrease pressure, not increase it. The idea that air molecules would stop colliding is incorrect, as they continue to collide, but more energetically as the temperature rises. Lastly, although air molecules do experience some expansion with increased temperature, this does not lead to a decrease in pressure; rather, the increased energy and movement lead to an increase in pressure overall.