explain situation of inertia: the slow of acceleration of a large truck compared to that of a car?

Answer 1

Well, heavier objects have more inertia than lighter ones. Intertia is the ability of an object to resist changes in it's speed and direction of that speed(known in physics as velocity, which is a vector quantity including speed and direction). The heavier the object, the more it resists changes in velocity.
On a more practical note, there's no reason a truck couldn't accelerate as fast as a car. It just takes more force/power to make a truck do the same thing as a car. Typically though, trucks weigh 5-20 times as much as a car. But they don't have 5-20 times as much power in their engines, more like 1-3 times. So they accelerater slower.