Question

y a small vehicle requires less force to attain acceleration while a heavy vehicle requires more force to get the same acceleration

Answer 1

as you know the formula of Newton's second law of motion f =ma
therefore a=f/m
this means that acceleration is directly proportional to Force inversely proportional to mass. which means if mass is greater then more force will be required to accelerate the body. this is the reason why small vehicles require less force to accelerate and heavy vehicles require more force to accelerate to get the same acceleration.

hope it helps:)