when you throw something up in a car that is going real fast why doesn't it fly back ?

Answer 1

It is already going the same speed as the car, as are you and the air in the car.

Answer 2

Because when it leaves your hand, it is travelling forward at the same speed as the car and will continue in that state of motion.
And if you throw it high enough you will find that it does fly back because its acted upon by wind resistance while the car is being propelled forwards by the engines power constantly.
In the absence of wind resistance and assuming the vehicle is going in a straight line, it will always come straight back to your hand.

Answer 3

Assuming that the car is traveling parallel to the ground,
the horizontal velocity of the object and the car is the same upon the release of the object from your hand. As the object travels vertically without hitting the car's ceiling, it will lose only a little of its horizontal velocity due to air resistance. Since the vertical travel is minimal inside the car, the horizontal(backward) displacement is hardly noticeable.

Answer 4

This is known as the principle of momentum and inertia. A mass moving at some velocity has momentum equal to that mass times that velocity. Unless something acts directly on it to change its momentum, it will continue in that state. That is known as inertia. In the case you cite, the only other force acting on the momentum of whatever you "throw up" is gravity, which pulls it downward at 9.8 meter/sec^2 until it hits the car interior, which stops it.

Answer 5

Because the car and ALL of its contents are traveling at the same speed ! Even the air (or atmosphere) within the vehicle !! Toss the item OUT --- and it --- "flys back" !!

Answer 6

objects in motion stay in motion...the car, and everything inside it...