will an 80kg guy of a 30 kg guy fall faster to the ground assuming that there is no air resistance.?

If they were in the same place and time, 'same' mathematically, they would fall at same speed.

If they were in different places or time, the forces exert on them may be different e.g. the moon which cause tides, and the gravitational acceleration 'g' is different from place to place.

My answer is different, coz' I am not a physicist but an engineer. I take everything into account. Of course, there are many forces beside gravitation and air resistant.

"No air resistant" doesn't mean that there is only gravity. Besides, gravity different from place to place.

Consider two objects having masses 1kg and 5 kg are in a horizontal plane.

We apply a force of 10 newton to the 1 kg mass and 50 newton to the 5kg mass.

That is, we apply less force for less mass and greater force for greater mass.

Now we find the acceleration of the two bodies.

The1 kg mass will have an acceleration of 10/1 = 10 m/ s^2. That is its speed will be going on increasing by 10meter / second in every second.

Similarly the 5 kg mass will have an acceleration of 50/5 = 10 m/s^2. That is its speed will be going on increasing by 10meter / second in every second.

Both have the same acceleration and both have the same speed at any time after start.

Now returning to gravitational pull, let us place the 1kg mass in one pan of the balance and the 5kg mass in another pan.

The pan having 5kg mass will come down and the pan having 1kg mass will go up.

This is because the earth is pulling the 5 kg mass with a force of 50 newton and 1kg mass with a force of 10 newton.

If we drop the two objects from the same place, as we have seen already the 1 kg mass will fall down with an acceleration of 10 m/ s^2 and the 5kg mass will also fall down with 10 m/ s^2. But the forces acting on them are different.

The Earth’s pull is such that it gives less force for less mass and greater force for greater mass.

To be more specific, it gives a force of 10 newton for every kilogram of mass and hence the acceleration is for any mass is the same as approximately 10m/s^2.

If you want rational answer backed by equation it is simply g = 10m/s^2.

From this it follows acceleration due to grvity is a constant.

Since in this equation, we dont have any term like mass, it follows that g is independent of any mass. In other word g is the same for all masses.

Simple! Both will fall at the same time.

no air resistance means there is no force opposing the fall ,therefore both bodies will accelerate at the same rate.both bodies will reach the ground together.

No. In a vacuum, each particle of matter will fall at the
same rate. It doesn't matter whether there is 80kg or 30kg
of matter in the bodies. The classic example is, lead and
feathers will both fall at the same rate, in a vacuum.

Drop an orange. Measure speed Now cut the orange in half.
Now repeat the experiment. The two halves will fall at the
same speed, just as though they are still connected as a whole orange.

Without air resistance, the two guys will fall at the same rate. On one of the moon missions, an astronaut dropped a feather and a hammer -- they fell at the same rate because there is no air resistance on the moon. That was a cool video.

You can use SUVAT to calculate the end velocity of the two men (they will be the same as SUVAT does not take into account air resistance).

s=ut + 0.5at^2

Galileo has already answered ur question:

One of the most famous stories about Galileo is that he dropped balls of different masses from the Leaning Tower of Pisa to demonstrate that their time of descent was independent of their mass (excluding the limited effect of air resistance). This was contrary to what Aristotle had taught: that heavy objects fall faster than lighter ones, in direct proportion to weight.

Though the story of the tower first appeared in a biography by Galileo's pupil Vincenzo Viviani, it is not now generally accepted as true. Moreover, Giambattista Benedetti had reached the same scientific conclusion years before, in 1553. However, Galileo did perform experiments involving rolling balls down inclined planes, which proved the same thing: falling or rolling objects (rolling is a slower version of falling, as long as the distribution of mass in the objects is the same) are accelerated independently of their mass. (Although Galileo was the first person to demonstrate this via experiment, he was not - contrary to popular belief - the first to argue that it was true. John Philoponus had argued this centuries earlier).

He determined the correct mathematical law for acceleration: the total distance covered, starting from rest, is proportional to the square of the time (This law is regarded as a predecessor to the many later scientific laws expressed in mathematical form.). He also concluded that objects retain their velocity unless a force – often friction – acts upon them, refuting the accepted Aristotelian hypothesis that objects "naturally" slow down and stop unless a force acts upon them (again John Philoponus had proposed a similar, though erroneous, theory). Galileo's Principle of Inertia stated: "A body moving on a level surface will continue in the same direction at constant speed unless disturbed." This principle was incorporated into Newton's laws of motion (1st law).

The skinny of this means that they both hit the ground at the same time ur fat guy just hits harder due to f=ma.

hopefully answers ur question and gives you the reason why

Both of them will fall together if dropped from the same height and are allowed to fall free.
Earth pulls all bodies towards its center with a certain force called the gravitational force/pull.the acceleration provided by the earth is approximately 10metre/sec/sec
the equation of motion relevant here is
the time taken t=square root of 2s/g ,where s is the distance through which they fall(which is the same) and g is the acceleration due to gravity which is a constant.
so you find that the equation of motion is independent of the mass of the falling bodies

they will both fall at the same time. the formula for this :
x = 1/2.a.t^2, where x is the height they are falling,a is the acceleration and t is time. in this formula x is the same for both and a is also same(app. 9.8) as u can see there is not affect of mass in the formula.thus,only thing that is left in the formula is time,which is the same for every object.(u can have 1 gram ball and 100000 kg ball,they will again fall at the same. the reason a paper will fall to the ground later is that,there occurs a greater resistance on the surface of paper)

I HAVE IT FOR YOU PLAIN AND SIMPLE!

F=ma, Newton's law.

F=mg
mg=ma
m cancles out. Acceleration to ground is independant of mass!

I lost a mark for this in my exam! Never again!

Yea as everybody has pretty much said, they will fall at the same accelleration (9.8ms-2) if there is no air resistance. A lot of people do not believe this, so here is an example of how much air resistance effects how fast something falls. It is a video of an Astronaut dropping a hammer and a feather on the moon, and they both fall at the same accelleration.

http://nssdc.gsfc.nasa.gov/planetary/image/featherdrop_sound.mov

1/2 GT2

Newton says, they will both arrive at the same time.

If both fall from the exactly the same height above the surface they'll fall at the same velocity. One of the Apollo astronauts proved that on the moon where's there's no air resistance when he dropped a feather and a hammer from the same height. Both hit the lunar surface together.

no the speeds should stay the same its just the force needed to stop them that's different

assuming no air resistance, both will reach the ground at the same time cos gravity is the same for both regardless of weight and size.

Nope, since they will be "Free Falling" all objects will fall at an acceleration of (9.8 meters/second^2). This is the only equation that can be used.

Fall at same speed, basic law of physics. All objects fall due to acceleration sue to gravity, 9.803 meters per second sqaure. mass has no effect.

No. They should be at the same speed, so should on ground at the same time. (if they fall at the same time and level)

Over what period of distance? Obviously we need to know this in order to do your math for you. Hook it up, DJ. -beaver (Rock Island, Illinois)

also: are we talking ONE "g" or more?

With no air resistance to take into consideration I would, on a gut reaction, assume that the 30kg guy would accelerate faster at the start of the fall then the 80kg guy, but that the 80kg guy would over take the other fella and land first due to pure mass theory. The earth (or gravitational force of your choice) would simply have more influence over the body containing more MASS. This of course is thrown to the wolves, so to speak, if the ground is "above" the point at which the 80kg guy overtakes the 30kg guy... That's why I asked the original question of "over what period of distance" are they falling....