The truck doesn't "exert more force".
It TAKES more force to accelerate the truck at the same rate
as the car, because the truck has more mass.
Think:
In order to move two rocks, you have to push harder on the heavy one
than you do on the lighter one.
How much more ?
In order to produce the same acceleration . . .
half as much mass ===> half as much force
twice as much mass ===> twice as much force
ten times as much mass ===> ten times as much force
a 1500-kg truck
compared to
a 500-kg car . . . triple the mass ===> triple the force, in order
to accelerate them equally .
