The average speed of a Nitrogen molecule in air is about 858 m/s, and its mass is about 4.68 × 10−26 kg.

If it takes 2.6 × 10−13 s for a nitrogen
molecule to hit a wall and rebound with
the same speed but in the opposite direc-
tion, what is the magnitude of the average
acceleration of the molecule during this time interval?

1 answer

I have a problem with the statement. The molecule only rebounds from the wall if it were moving perpendicular to the wall in the first place. In a gas, this would be most unusual, most are moving in all directions, and "glance" off the wall. Neglecting that reality...

change of velocity=2*original speed

and the direction of the change in vleocity is outward from the wall.

a= change speed/time