The force of impact will be the same for both vehicles. But the acceleration of each will be different because each has a different mass.

BIG TRUCK force = tiny car force.

But F=ma

so m(BIG TRUCK) x a1 = m(tiny car) x a2

If you knew more data you could solve but you could also figure that the accelerations "a" will be proportional to the ratio of the masses. If the truck had a mass 10 times that of the car the car would see 10 times the acceleration, not a fun day for people in the tiny car!

BIG TRUCK force = tiny car force.

But F=ma

so m(BIG TRUCK) x a1 = m(tiny car) x a2

If you knew more data you could solve but you could also figure that the accelerations "a" will be proportional to the ratio of the masses. If the truck had a mass 10 times that of the car the car would see 10 times the acceleration, not a fun day for people in the tiny car!