If a body crashes through a skyscraper window, what falls first? The body or the glass shards from the window?

Question

Just curious, you know.

Answer 1

Both.

The guy, unless he was moving downward AT THE TIME HE HIT THE WINDOW, had an initial vertical velocity of zero.

The glass had an initial vertical velocity of zero.

Both objects are affected the exact same way by gravity; both will accelerate downward at 9.8m/s^2.

So both will have the exact same velocity at all points along their fall downward, and both the body and the glass shards will hit the ground at the same time. The only way that one could strike before the other is if aerodynamic effects took hold, but I think that because the glass has flat, nonaerodynamic sides, and would be tumbling, it wouldn't be an issue.

Answer 2

Markii is very wrong. Gravity has the same pull on every single object (anyone who has ever studied physics will tell you the same thing). What causes differences in fall times has nothing to do with gravity. It's due to air resistance. This is based off a few factors, but mostly deals with weight distribution. Since we have a lot of mass compacted into a very small area, wind resistance on us is very little compared to something like glass or paper. Glass is lighter, and much less dense, and since it is flat, the air has more of a surface area to come in contact with, and as a result, may fall slower. Really small glass takes even longer because factors like wind force can overcome the acceleration due to gravity and blow it in different directions.

It could fall faster though, as if the glass falls sideways, it could kind of "slice" through the air, because the thin side of glass has almost no surface area for air resistance to come in contact with.

Also, Stephen is sort of right. The glass shattering absorbed some of his kinetic energy, so some of the glass would most likely have a higher starting velocity, which could very well mean it hits first. It depends on how high the skyscraper is and how long it has before hitting terminal velocity.

So, some glass may fall faster, but some may fall slower. Sorry you can't get a definite answer to this.

Answer 3

Some of the glass may fall after the body because it was thrown further away from the building or went down on an angle but both descend at the same rate. Weight has nothing to do with it.

Drop a golf ball and a bowling ball and both will hit the ground at the same time.

Seriously try it.

Answer 4

Most of the glass shards will hit the ground before the body, because they are more aerodynamic and therefore will have a greater terminal velocity.

All falling objects experience the exact same downwards acceleration due to gravity: 9.8 m/s^2. (Each object experiences a gravitational force that is proportional to its mass, and acceleration is inversely proportional to mass, so every body falling under gravity alone experiences exactly equal acceleration near the surface of the Earth.)

All falling objects also experience an upwards force caused by drag, also called fluid friction or air resistance. This force depends on velocity and surface area, and more aerodynamic objects experience proportionally less drag force per unit mass, causing them to experience less upwards acceleration and therefore a greater net downwards acceleration.

The particular velocity at which the downwards gravitational force and the upwards drag force on an object are equal is called terminal velocity, and an object falling at terminal velocity experiences no net acceleration because it is at equilibrium. Terminal velocity is unique to a given object, and the glass shards should have a higher terminal velocity than a falling body--although a skyscraper is not necessarily tall enough for the objects to reach their terminal velocities.

Answer 5

Both have same acceleration, so it depends on the velocity of the shards vs the body.

Presumably the body pushes the shards to the same velocity as the body (as in an inelastic collision) in which case, they both hit the ground at the same time.

Answer 6

How fast was the body going before it hit the glass? How much did the glass slow it down? Did the glass shatter into 'pebbles' or large shards?

All of these variables (and more) changes the answer!!

Answer 7

The body. Gravity has a stonger pull on heavy objects like a human body, & the really light glass shards will hit the ground about 30 seconds, give or take depending on how high the skyscraper is.

Answer 8

the glass, as its just started its motion...but the body has been slowed by the impact.

Answer 9

The person, he is traveling alot faster and weighs more.

Answer 10

the body......!