Most of us know intuitively that ina head-on collision between a large dump truck and a subcompactcar, you are better off being in the truck than in the car. Why?Many people imagine that the collision force exerted on the car ismuch greater than that experienced by the truck. To substantiatethis view, they point out that the car is crushed, whereas thetruck in only dented. This idea of unequal forces, of course, isfalse. Newton's third law tells us that both objects experienceforces of the same magnitude. The truck suffers less damage becauseit is made of stronger metal. What about the two drivers? Do theyexperience the same forces? To answer this question, suppose eachvehicle is initially moving at 6.0 m/sand they undergo a perfectly inelastic head-on collision. Eachdriver has mass 90.0 kg. Including thedrivers, the total vehicle masses are 810 kg for the car and 4010kg for the truck.

If the collision time is 0.120 s, whatforce does the seatbelt exert on the truck driver?

N

What average force does the seatbelt exert on the car driver?

N