Physics

Bwcad1 · Post by **Bwcad1** » Thu Sep 29, 2005 6:16 am

Ok guys answer me this I have fought with every one of my family members about this. Its basic physics… if you are riding in a car that is moving at about 35 miles per hour and you jump your going to stay in the same spot correct? My family is trying to tell me that if you jump you will fly to the back of the car… it doesn’t make any sense your moving at the same speed of the car. Its just like throwing a penny up in the air in a car it stays in the same spot cause its moving at the same speed. That’s correct right? In a crash you fly forward because the car has lost its speed and there is nothing to stop your body. If my family was correct in the event of a crash you would just stay were you are unless something hit you. I don’t understand how they think this to me its just basic physics and commons sense. They only time you would fly back is if you were under constant acceleration.

I also had this fight with my old integrated science class. If you shoot a bullet and drop one out of you hand at the same time they will hit the ground at the same time? I know for a fact that’s crap because I have a rifle that will shot 2 miles which means it covers a distance of 10560 feet. The average bullet falls to earth at 2.5 miles per hour so it takes 2 seconds to drop 5 feet. That shot bullet has to go 1 mile a second? Or 19,008,000MPH (if my math is correct). Im pretty sure there is no gun that shoots nearly that speed.

Ryan from Ohio · Post by **Ryan from Ohio** » Thu Sep 29, 2005 6:44 am

The first is so simple anyone can try the experiment. Youre correct, end of it.

Throw a coin up it doesnt fly to the back of the car. Thats because all the objects are moving at the same rate.

As far as the gun. If you drop a bullet and fire a gun the dropped bullet will hit the ground first. Because the fired bullet has an implied force the dropped bullet does not.

Bwcad1 · Post by **Bwcad1** » Thu Sep 29, 2005 6:46 am

sometimes i just dont understand people. it doesnt make sense to me its commons sense.

Ryan from Ohio · Post by **Ryan from Ohio** » Thu Sep 29, 2005 7:24 am

What you fail to realize is not everyone is as smart as you are.

True there are smarter people out there, but there is also stupid people.

What some of us consider common sense/knowledge is just not thinkable to some.

Justin from Detroit1 · Thu Sep 29, 2005 7:24 am

An object in motion tends to stay in motion unless acted upon by an outside force.

Bwcad1 · Post by **Bwcad1** » Thu Sep 29, 2005 8:23 am

exactly^ I do realize how smart i am and i realize how stupid some people are what im shocked about is the amout of people that agree with my family there the majority... no me and you

Post by **GlassWolf** » Thu Sep 29, 2005 9:46 am

one of the more basic rules of physics.
an object in motion tends to stay that way.. in motion.

if the car is traveling at 35MPH and you jump up, you're still traveling at 35MPH along with the car.. you'll begin to decellerate, but not at enough of a rate to really notice unless you stay airborn for a fairly substantial period of time.

A typical jump in the air while in a moving car will last about .5 seconds. In that period, you'll still be going approximately the same speed as the vehicle.

If your family were right, every time someone got on an airplane and got up to go to the bathroom, they'd be hurtled right through the tail of the plane at a rate of about 400MPH.
We won't even get into what'd happen if they took a dump while riding in an airplane at 15,000 feet, going 400+MPH.

Post by **GlassWolf** » Thu Sep 29, 2005 9:48 am

ask your family why, if things not fastened to the car would decellerate instantaneously, why things like a magazine laying on the floor of the car doesn't fly back and smash the rear window of the car the moment nothing is nailing it to the vehicle.

Bwcad1 · Post by **Bwcad1** » Thu Sep 29, 2005 9:48 am

Lol Thank You So Very Much Im Going To Finish This Fight With My Family And Tell Them How It Is. Glad Im Not The Crazy One!

lotas · Post by **lotas** » Thu Sep 29, 2005 11:29 am

Bwcad1 wrote:Ok guys answer me this I have fought with every one of my family members about this. Its basic physics… if you are riding in a car that is moving at about 35 miles per hour and you jump your going to stay in the same spot correct? My family is trying to tell me that if you jump you will fly to the back of the car… it doesn’t make any sense your moving at the same speed of the car. Its just like throwing a penny up in the air in a car it stays in the same spot cause its moving at the same speed. That’s correct right? In a crash you fly forward because the car has lost its speed and there is nothing to stop your body. If my family was correct in the event of a crash you would just stay were you are unless something hit you. I don’t understand how they think this to me its just basic physics and commons sense. They only time you would fly back is if you were under constant acceleration.

I also had this fight with my old integrated science class. If you shoot a bullet and drop one out of you hand at the same time they will hit the ground at the same time? I know for a fact that’s crap because I have a rifle that will shot 2 miles which means it covers a distance of 10560 feet. The average bullet falls to earth at 2.5 miles per hour so it takes 2 seconds to drop 5 feet. That shot bullet has to go 1 mile a second? Or 19,008,000MPH (if my math is correct). Im pretty sure there is no gun that shoots nearly that speed.

actually if you fire a bullet and drop one at the exact instant the other comes out of the barrel they will hit the ground at the same time. The one that comes out of the gun will just be way furthur away (way way furthur away). I know that sounds incredibly odd, and its almost uncomprehendable but they both have the same vertical acceleration (-9.81m/s^2).

in fact thats incredibly ironic because we just talked about that same exact scenario in physics yesterday.