Why isn’t a penny dropped from space able to kill you?

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Why isn’t a penny dropped from space able to kill you?

In: Physics

8 Answers

Anonymous 0 Comments

Side note to the main answer already posted, I imagine it would also burn up before reaching group if dropped high enough

Anonymous 0 Comments

People have mentioned terminal velocity but there is another factor, mass.

The mass of an object determines the amount of energy that it imparts into it’s target. You can hit someone as hard as you can with a pool noodle, a wooden baseball bat and a lead pipe and the results would be different because of their mass.

Anonymous 0 Comments

When an object falls through air, it eventually reaches a speed were the acceleration from the force of gravity is canceled out by the force of air resistance—it is called terminal velocity. So, this could mean that an object that falls from 100 metres and an object that falls from 100 km hit the ground at the same speed.

The terminal velocity of a penny is at most 80 km/hr. Since a penny has very little mass, a penny moving at 80 km/hr does not have that much momentum, and thus creates less of an impact force. In comparison, a paintball has a muzzle velocity of about 300 km/hr, and a paintball weighs more than a penny. If you can survive beings shot with a paintball, you can certainly withstand a penny impact.

Anonymous 0 Comments

You ask this like you’ve tried it?

Anonymous 0 Comments

Air resistance. Think about a piece of paper. If I drop it from shoulder height, it doesn’t go very fast, right? If I drop it from the top of my house, it might go a little faster, but there’s a limit to how fast that piece of paper can fall. The air is getting in the way, preventing my paper from falling any faster!

This speed is called the *terminal velocity.* The faster an object goes, the more air resistance it encounters. You can think of this like a rubber band: the more you stretch it, the harder it becomes to stretch. At some point, an object reaches a speed where the air resistance directly counteracts the gravity. That’s like when you can’t stretch the rubber band anymore because it’s gotten too difficult.

A penny’s terminal velocity isn’t powerful enough to kill you.

Anonymous 0 Comments

Newton’s 1st law.

An object will stay in motion until it is acted on by an outside force. In this case the air creating friction on the penny. Same principle that forces your hand back when you stick out a car window. No matter how much momentum it gains from falling to earth the atmosphere will slow it down. It will only ever go so fast. In science it’s called “terminal velocity”.

Anonymous 0 Comments

>Why isn’t a penny dropped from space able to kill you?

Because earth has an atmosphere and the constant friction caused by an object’s drag during the fall means that there is a hard limit on how much it can be accelerated. At some point it will reach its terminal velocity and that’s it. A penny dropped from 100km will have the same velocity (and therefore the same kinetic energy) on impact as a penny dropped from 1km.

Anonymous 0 Comments

Because a penny is primarily made of two flat sides, those sides are always more likely to be facing downward than the edge. The flat edges act like a parachute to slow the penny down as it falls, and falling all the way through the atmosphere with that much drag would cause the penny to break up into tiny pieces of copper and zinc far before it hit the ground.