#1

This is really easy stuff, but my mind is completely blank for some reason, and I need to get it done by tomorrow.

A self-propelled balloon car goes 4.3 meters. It took 2.35 seconds to cover 3 meters. It's mass is 7.9g.

So here's what I need to find out:

Car's average speed: .78

Car's weight in Newtons and mass in kilograms: .07742 N and .0079 kg, right?

Car's final velocity at the end of the 2.35 seconds: No idea. Don't I need to find the acceleration rate first though?

Car's Kinetic Energy: 1/2mv^2, so .00395? X_X

Car's final momentum: .0061857 kg m/s or whatever the damn unit is?

Total work done by balloon: ?

Potential Energy of the balloon before the start: =KE?

Total power balloon produced: ?

You guys are smart, please help me!

<33

A self-propelled balloon car goes 4.3 meters. It took 2.35 seconds to cover 3 meters. It's mass is 7.9g.

So here's what I need to find out:

Car's average speed: .78

__3__m/s, correct? time/distance; 2.35/3?Car's weight in Newtons and mass in kilograms: .07742 N and .0079 kg, right?

Car's final velocity at the end of the 2.35 seconds: No idea. Don't I need to find the acceleration rate first though?

Car's Kinetic Energy: 1/2mv^2, so .00395? X_X

Car's final momentum: .0061857 kg m/s or whatever the damn unit is?

Total work done by balloon: ?

Potential Energy of the balloon before the start: =KE?

Total power balloon produced: ?

You guys are smart, please help me!

<33

#2

I plan on getting by with my looks.

#3

The answer > speed of sound.

I hate physics.

I hate physics.

#4

I plan on getting by with my looks.

...

#5

I need feet and pounds, damn metric system!

#6

I plan on getting by with my looks.

Same, but my physics teachers a dood.

What has this country come to?

#7

Ok well the answer is

299,792,459m/s

299,792,459m/s

#8

Is this just an equation you were given or did you actually do this expierment.

If you did....your a noob. Mine went 12 meters

If you did....your a noob. Mine went 12 meters

#9

The obvious answer is the balloon produced enough energy to move the car.

#10

Ew. Don't remind me of physics. I have a final tomorrow in that class that I'm going to fail ><

#11

Is this just an equation you were given or did you actually do this expierment.

If you did....your a noob. Mine went 12 meters

We did an experiment. We had extremely limited rescources, and this is what we got on our first try.

#12

X?

#13

Same, but my physics teachers a dood.

What has this country come to?

Together, us beautiful people will crush on through, forging a path unworthy of gazing upon us.

/endpompousness

#14

Together, us beautiful people will crush on through, forging a path unworthy of gazing upon us.

/endpompousness

Yeah, thanks. But I need to get through school first.

So until then, NERDS OF THE PIT, UNITE! and help me with my homework

#15

This is really easy stuff, but my mind is completely blank for some reason, and I need to get it done by tomorrow.

A self-propelled balloon car goes 4.3 meters. It took 2.35 seconds to cover 3 meters. It's mass is 7.9g.

So here's what I need to find out:

Car's final velocity at the end of the 2.35 seconds: No idea. Don't I need to find the acceleration rate first though?x=x(i)+v(i)t+at^2, solve for a. then v=v(i)+at. Maybe try another kinematics equation, if those don't work

Total work done by balloon: ?W=Fx

Potential Energy of the balloon before the start: =KE?Ug=mgh is potential energy

Total power balloon produced: ?P=W/t

x=final position

x(i)=initial position

v(i)=initial velocity

v=final velocity

t=time

a=acceleration

W=work

Ug=Potential Energy

m=mass

g=acceleration due to gravity

h=height

P=Power

I don't feel like plugging in all the numbers, but that should help a little, those are the right equations bolded I believe. Unfortunately my AP physics class isn't really advanced where we would use the calculus methods with derivatives and whatnot, so we just kind of have basic equations and whatnot. If you're in a higher level thing maybe that doesn't help.

*Last edited by SickMetal at Jan 24, 2007,*

#16

It's pathetic I can't answer this considering we covered this several chapters ago

#17

d=vit+(1/2at2)

the second 2 is an exponent.

that might help

cause the initial velocity(vi) =0

therefore you can cross that out... divide distance by tsquared and multiply by 2

voila

acceleration

thatshouldwork.

the second 2 is an exponent.

that might help

cause the initial velocity(vi) =0

therefore you can cross that out... divide distance by tsquared and multiply by 2

voila

acceleration

thatshouldwork.

#18

x=69

#19

I don't feel like plugging in all the numbers, but that should help a little, those are the right equations bolded I believe.

Dude, thank you so much!

Edit: Position is the same thing as distance, right?

*Last edited by QuiteTheFellow at Jan 24, 2007,*

#20

Physics?

#21

A self-propelled balloon car?

Don't be so ridiculous.

Don't be so ridiculous.

#22

Dude, thank you so much!

Edit: Position is the same thing as distance, right?

Yeah, basically. It's the distance from wherever you want to call zero (You could make it easier on yourself by defining the initial position as zero so it's not as confusing, lol).

Hope that helps.

I just got my ass busted by an AP physics midterm the other day so I'm not going too crazy here lol, those are all equations and stuff, if you need more help you can ask.

#23

^(to the dude with the elephant)

One more question, how do I find force? =(

One more question, how do I find force? =(

#24

Physics?

ROFL.

What you can do is use a conservation of energy principle.

Ei=Ef

So, the potential energy of this thing at rest on top of the ledge or whatever would be equal to the potential energy when it's on the spring.

So,

Ug=Us

mgh=kx^2

Solve for x

^^F=ma. Newton's laws and whatnot.

#25

I'm actually interested in those raptor questions.

I'm sure it's easy, but it kills me how awesome those questions are.

EDIT: The whole "The raptors run a 10m/s, and they know no fear" part is funny as hell, as well.

I wish I had floor plan as well.

I'm sure it's easy, but it kills me how awesome those questions are.

EDIT: The whole "The raptors run a 10m/s, and they know no fear" part is funny as hell, as well.

I wish I had floor plan as well.

*Last edited by fallenangel20 at Jan 24, 2007,*

#26

Average velocity = 1.2765

Weight + Mass = .07742 N , .0079 kg

This question doesn't give all the right information for final velocity and potential energy(there's no height so the formula PE=mgh doesnt apply) (and there's no initial or final velocity for the 2.35 seconds of travel)

Work = .03397 Joules

Power = .425531 Watts

Weight + Mass = .07742 N , .0079 kg

This question doesn't give all the right information for final velocity and potential energy(there's no height so the formula PE=mgh doesnt apply) (and there's no initial or final velocity for the 2.35 seconds of travel)

Work = .03397 Joules

Power = .425531 Watts

#27

Average velocity = 1.2765

Weight + Mass = .07742 N , .0079 kg

This question doesn't give all the right information for final velocity and potential energy(there's no height so the formula PE=mgh doesnt apply) (and there's no initial or final velocity for the 2.35 seconds of travel)

Work = .03397 Joules

Power = .425531 Watts

Thanks!

The initial velocity is given as 0, final velocity isn't given.

As for the PE formula, I think I need to find the elastic potential energy, not gravitational. Don't remember that formula though =(

Also, how did you find the average velocity? My brain needs a refresher.

#28

that is AWESOME

#29

I'm actually interested in those raptor questions.

I'm sure it's easy, but it kills me how awesome those questions are.

EDIT: The whole "The raptors run a 10m/s, and they know no fear" part is funny as hell, as well.

I wish I had floor plan as well.

no matter what they would get you faster seeing as you only run 6 m/s and the slowest raptor goes 10 m/s, plus it would take the other two raptos 4.5 seconds to get to the center which is way enoguh time to regroup and get you no matter which way nyou ran

#30

no matter what they would get you faster seeing as you only run 6 m/s and the slowest raptor goes 10 m/s, plus it would take the other two raptos 4.5 seconds to get to the center which is way enoguh time to regroup and get you no matter which way nyou ran

True, but also, depending on the terrain, it could take some time.

But since they don't give a certain land type, I guess we can just use plain, flat, dirt area.

I love the last question, though. Just the idea to make a floorplan to escape, and taking into account they adapt to the doors and all, it's genius.

#31

1. Find when the position of you and the raptor are the same.

Find how far the velociraptor went in the time it took him to reach top speed.

v=v(i)+at^2

25 m/s=0 +(4m/s^2)(t^2)

(25/4)^(1/2)=t

t=2.5

d=d(i)+v(i)t+at^2

Plug it in.

Then find out how far you went in 2.5 seconds.

Then set the position formula equation equal to itself with one side being the guy (with all the data at their values at 2.5)and one side being the raptor(again, at 2.5s) and solve for t. Then add that t to 2.5 and plug it in to find how far you went.

2. I'm sure that's pretty easy but I don't have the time/patience to look at it now, lol.

3. Lol, you can figure that out.

To the other dude, the formula for the potential energy of a spring is Us=kx^2 with k being the spring constant and x being the distance that the elastic thing is compressed by whatever's pushed into it.

#32

Damn.... this makes me want to know physics....I've always found it interesting, but I've enver had the chance to learn. I'm in the only 10th grade....Biology....meh. IT's okay, but the teacher's too stubborn, she ALWAYS has to be right, and biology just isn't my thing.

#33

Thanks!

The initial velocity is given as 0, final velocity isn't given.

As for the PE formula, I think I need to find the elastic potential energy, not gravitational. Don't remember that formula though =(

Also, how did you find the average velocity? My brain needs a refresher.

Vavg=d/t

ok so for the other question you use D=1/2(a)(t)^2 4.3=1/2(a)(2.35)^2

4.3=2.761(a) A=1.557 the you use Vf=Vi + (a)(t) Vf=0 + (1.557)(2.35)

Vf = 3.65 Vf is final velocity by the way

#34

Yeah dude, I'll be honest, I thought 9th grade honors bio and 10th grade honors Chemistry sucked, but I'm in 11th grade AP Physics and I actually like it. I'd probably appreciate the other two more now because they always just teach you the easy basics, and the fact is that the other two have a lot of things that come directly from physics, so the subjects aren't really that different from each other, it's all branching off the same thing.

#35

I was going to take physics next year, but I am taking Pre-calc, and didn't really want two math courses (pretty much) so I decided to take pshycology instead, which should be awesome.

#36

Vavg=d/t

ok so for the other question you use D=1/2(a)(t)^2 4.3=1/2(a)(2.35)^2

4.3=2.761(a) A=1.557 the you use Vf=Vi + (a)(t) Vf=0 + (1.557)(2.35)

Vf = 3.65 Vf is final velocity by the way

For the Vf I got 2.557m/s =(

I did:

a=2d/t^2

a=6/5.52

a=1.09

Then:

[sqr() means square root]

Vf=sqr(2ad)

Vf=sqr(6a)

Vf=sqr(6*1.09)

Vf=sqr(6.54)

Vf=2.557

What did I do wrong? =(

Also, whats the formula for force?

#37

^^F=ma

#38

F=ma

Force=mass • acceleration

Sickmetal, are you taking Physics B? I'm in Pre-AP Physics this year, and I'm taking AP Physics C next year.

Force=mass • acceleration

Sickmetal, are you taking Physics B? I'm in Pre-AP Physics this year, and I'm taking AP Physics C next year.

#39

Yeah, I'm in Physics B. Definitely gonna take C next year. I'm taking Calculus AB this year so the math part shouldn't be too tough, I just want to see how they correspond to each other.

To the dude with the Pre-Calc and the not taking Physics...the math part of Physics isn't very difficult as long as you're not doing courses that involve derivatives and integration and stuff (which you shouldn't be if it's the first time you take physics, like me), it's basically a Science course that uses some math skills, nothing crazily difficult.

To the dude with the Pre-Calc and the not taking Physics...the math part of Physics isn't very difficult as long as you're not doing courses that involve derivatives and integration and stuff (which you shouldn't be if it's the first time you take physics, like me), it's basically a Science course that uses some math skills, nothing crazily difficult.

#40

Average velocity = 1.2765

Weight + Mass = .07742 N , .0079 kg

This question doesn't give all the right information for final velocity and potential energy(there's no height so the formula PE=mgh doesnt apply) (and there's no initial or final velocity for the 2.35 seconds of travel)

Work = .03397 Joules

Power = .425531 Watts

PE=KE = 1/2 mv^2 physics noob