In a zero gravity vacuum like space, would it take the same force to push a baseball and a firetruck?

Question

Basically I want to know, in a zero weight environment, do heavier objects (based on their earth weight) require more energy to move, tow, push, etc, than lighter objects (baseball versus firetruck)?

If you have sources for your answer please post.

Answer 1

First off all, there is no such thing as a zero gravity environment....gravitational forces can be felt anywhere and everywhere in the universe, in order to completely escape gravity, one would need to go an infinite distance away from all mass.
And for that matter, nothing is every a true, perfect, vacuum either.

But back to the question.....

Newton's 2nd law of motion is,
F = m * a
Force = mass * acceleration
A force applied to a mass causes acceleration.
You can see that for a constant force, F, the resulting acceleration depends upon the mass of the object.....a larger mass will accelerate less than a smaller mass for a given force.

Mass and weight are not the same thing.
In space, you might appear to be "weightless", but you are never massless. No matter where one is in the universe, your mass is constant.
A baseball will have a much smaller mass than a fire truck.
Therefore, for a given force, a base ball will accelerate much more than a fire truck.

One could also think of it in terms of energy (rather than a force causing acceleration and a change in momentum).
A force applied over a distance does work on a mass.
Work = Force * distance.
Doing work on an object increases its energy....pushing on an object with a force will accelerate and thus increase its kinetic energy (KE).
KE = 1/2 mv^2
Where m is the objects mass and v is the objects speed.
One can equate the work done by the force to the change in kinetic energy,
F * d = 1/2mv^2
In order to accelerate both objects to the same final speed with a given constant force, the two objects must have the same amount of work done on them. If the force and both objects’ masses are given and we want their final speeds to be equal, the smaller mass must be pushed a farther distance in order for the same work to be done on it since the accelerations are not equal.
v = a*t
Velocity = acceleration * time

Answer 2

Noone is right yet...

edit: except the guy that posted just before me.

There is most definitely gravity in space... zero gravity is a very iffy term to use. However, whwen one is in orbit the speed of the orbit is counteracting gravity... so it is technically "weightlessness"... At this point if you had a baseball and a firetruck, if you gave a firetruck a 1 N push it would affect your motion a lot more than the firetruck... A baseball would be affected much more than you in the other case, however the motion would be transferred to both objects no matter what you push on.

Answer 3

Just because an object doesn't have "weight" doesn't mean it doesn't have "mass." On Earth we tend to think in terms of weight=mass, but in a zero gravity environment, although a baseball and a firetruck would both have a weight of zero, the firetruck would still be just as much more massive than the baseball as ever, and just as much harder to get moving (and once moving, just as hard to stop.)
Think about this: If you were in space, would you rather be hit by a baseball travelling at 30 miles per hour or a firetruck travelling at 30 miles per hour? Same principle.

Answer 4

No, they would be the same to push

"earth weight" is based mass x gravity, therefor no gravity, there is no weight, vacuum does'nt really come into play.

Edit: Ignoring acceleration and assuming you are fixed, 1N would definetly move either object, as would any other force. Acceleration was'nt mentioned, although yes I do realize they are intertwined. It's all in the wording but that Jeffey guy is a little more thorough.

Answer 5

Newton's 2nd Law, F = m*a (actually he said time rate of change of momentum, but for constant mass, this is OK). Doesn't matter where the object is, mass is constant for non-relativistic speeds.

Firetruck has greater mass so it takes a greater force to accelerate it. Since the firetruck has greater mass, for the same velocity, it has greater energy than baseball.

Source is fundamental (high school) physical science and physics.

Answer 6

No, the firetruck would still require a greater force to push because the firetruck still has more inertia.

Answer 7

think about it u could throw a baseball but a firetruck it has more mass than u,u might push it but u would be moving from it faster than it would b moving from u

Answer 8

Yes

Answer 9

no everything is slower so it seems

Answer 10

no