Science problem.. :/

[vopos]

So I have a question to do that is part of my homework and I don't know how to do it so I have come to the forum so that someone can explain to me how I do it. Here's the question:

 

The aircraft has a take-off mass of 320,000 kg. Each of the 4 engines can produce a maximum force of 240kN.

 

Use the equation in the box to calculate the maximum acceleration of the aircraft.

 

(This is in the box) resultant force=mass x acceleration

 

 

So, can anyone help me??

 

[FireFox]

I used to be quite good at these but I have no idea

[Cyrus]

you have the mass and the force is 4x 240 000 so it should be 4  * 240 000= a * 320 000 <=> 960 000 = a * 320 000 <=> 960 000/320 000= a <=> a = 3 m/s

[Adnanklink]

4*240,000=320000*acceleration --->  acceleration = (4*240000)/320000

(sum of forces)=mass*acceleration

 

Also, i think we are assuming gravity has no effect as the force it applies is quite small and they don't give any angles to allow for vector algebra.

[ilikemacandpc]

max force = 4 * 240,000 N = 960,000 Newtons

 

mass of aircraft = 320,000 Kg

 

Acceleration = ?

 

F=ma

 

a=F/m

 

a=3 m/s/s

[coen113]

the mass is 320 000 kg, the force is (240 000*4)

 

960 000 000 = 320 000 * accelleration

 

this means that

960 000 000/320 000= 3 000cm/s

3000 cm/s /1000 = 3 m/s

[vopos]

Thanks guys!!!!!!!!!!!!!! Those were really fast answers oh my god

[Adnanklink]

Thanks guys!!!!!!!!!!!!!! Those were really fast answers oh my god

SCIENCE!!!!!!!!!!!!

[coen113]

Thanks guys!!!!!!!!!!!!!! Those were really fast answers oh my god

such speed. much skill. wow.

[Scionyde]

4*240,000=320000*acceleration --->  acceleration = (4*240000)/320000

(sum of forces)=mass*acceleration

 

Also, i think we are assuming gravity has no effect as the force it applies is quite small and they don't give any angles to allow for vector algebra.

 

Well, I haven't been in a physics classroom in 6 years, so I'm possibly off-base. Wouldn't it make sense to factor in gravitational force? F_g = (320,000 kg) * (9.81 m/s^2)

 

Granted, that ends up being greater than the force provided by the four engines, so maybe the teacher isn't intending on including it. I guess the problem never specifies it takes place on Earth?

 

EDIT: Maybe it has something to do with the phrase "take-off mass", which implies ignoring gravity? *shrug*

[TheMikeyG]

SCIENCE BITCH!

[daemonowner]

960 000 000/320 000= 3 000cm/s

3000 cm/s /1000 = 3 m/s

 

do you mean 3 cm/s coen?

[DoubleY]

SCIENCE BITCH!

You beat me to it

[Ciccioo]

Well, I haven't been in a physics classroom in 6 years, so I'm possibly off-base. Wouldn't it make sense to factor in gravitational force? F_g = (320,000 kg) * (9.81 m/s^2)

 

Granted, that ends up being greater than the force provided by the four engines, so maybe the teacher isn't intending on including it. I guess the problem never specifies it takes place on Earth?

 

EDIT: Maybe it has something to do with the phrase "take-off mass", which implies ignoring gravity? *shrug*

that is the force that pulls the aircraft down, it is ortogonal to the force that the engines produce, so there is no effect on the acceleration

it's relevand if you consider both gravity and friction, but that way you would need to multiply that gravitational force by a certain coefficient that would make it lower that the force provided by the engines

[kinkywink]

Well, I haven't been in a physics classroom in 6 years, so I'm possibly off-base. Wouldn't it make sense to factor in gravitational force? F_g = (320,000 kg) * (9.81 m/s^2)

 

Granted, that ends up being greater than the force provided by the four engines, so maybe the teacher isn't intending on including it. I guess the problem never specifies it takes place on Earth?

 

EDIT: Maybe it has something to do with the phrase "take-off mass", which implies ignoring gravity? *shrug*

for this level of physics they usually intend it to be in an "isolated system" and ignore gravity and friction etc, once they start doing vector triangles itll start including gravity and other stuff

[Adnanklink]

Well, I haven't been in a physics classroom in 6 years, so I'm possibly off-base. Wouldn't it make sense to factor in gravitational force? F_g = (320,000 kg) * (9.81 m/s^2)

 

Granted, that ends up being greater than the force provided by the four engines, so maybe the teacher isn't intending on including it. I guess the problem never specifies it takes place on Earth?

 

EDIT: Maybe it has something to do with the phrase "take-off mass", which implies ignoring gravity? *shrug*

Well as i kinda implied, the force that the engines provide is not completely vertical (as gravity is), its going to be at an angle meaning that the force from the engines has a vertical component(that gravity will affect) and a horizontal effect (unaffected by gravity). These two components cannot be calculated without knowing angle of lift off or values that will allow you to find it. 

 

Also, you are correct in saying that the force of gravity will be greater than the engine forces but it is actually much more complicated than that; there are other forces that are not mentioned such as the force opposing the air under the wings (1 of newtons laws that states that for every force, there is an equal and opposite force)

[Adnanklink]

960 000 000/320 000= 3 000cm/s

3000 cm/s /1000 = 3 m/s

 

do you mean 3 cm/s coen?

no, its 960kN or 960000N. Also something is wrong because the units for acceleration are m/s^2

[Scionyde]

that is the force that pulls the aircraft down, it is ortogonal to the force that the engines produce, so there is no effect on the acceleration

it's relevand if you consider both gravity and friction, but that way you would need to multiply that gravitational force by a certain coefficient that would make it lower that the force provided by the engines

 

Ah, I gotcha, I was picturing some sort of VTOL in my mind for some reason.

[Ciccioo]

i think that we turned a simple "do a single moltiplication" problem into a "phisics master degree must apply ALL the forces and do ALL the calculations" problem

[Adnanklink]

i think that we turned a simple "do a single moltiplication" problem into a "phisics master degree must apply ALL the forces and do ALL the calculations" problem

Lol, even funnier is that fact that this is all within the first college level physics course.

[Cyrus]

Lol, even funnier is that fact that this is all within the first college level physics course.

 

First year of high school lel ^^ im 16 .__.

[Ciccioo]

Lol, even funnier is that fact that this is all within the first college level physics course.

now we just need to apply some relativistic bullshit and we're done

so the OP will go back to the prof and explain him how the acceleration of the airplane slows down time and makes it grow in mass, so the answer to the problem is that the maximum acceleration is negative in space and negative in time, and the airplane will degenerate and become a freakin' eagle and use the passengers to feed all of its little birds in the prehistory

[wpirobotbuilder]

Just wait until these equations factor in the loss of mass due to exhaust. Then they get much more fun.

[IdeaStormer]

Just wait until these equations factor in the loss of mass due to exhaust. Then they get much more fun.

 

Coriolis effect anyone :lol:

[imthewalrus]

You forgot to mention if the gravity due to Jupiter is negligible or not.