Name: 航母起飛的加速度｜一維運動｜物理學｜可汗學院 (Acceleration of aircraft carrier take-off | One-dimensional motion | Physics | Khan Academy)
Uploaded: 2021-01-14T06:35:58.000Z
Duration: 14 min 16 s
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So I'm curious about how much acceleration

does a pilot, or the pilot and the plane,

a picture of an F/A-18 Hornet right over here.

It has a take-off speed of 260 kilometers per hour.

If we want that to be a velocity, 260 km/hour

in this direction, if it's taking off from

this Nimitz class carrier right over here.

the catapult length, because these planes

don't take off just with their own power.

so they can be really accelerated quickly

And the runway length of a Nimitz class carrier

And then they come in and they land over here.

So to do this, let's figure out, well let's just

figure out the acceleration, and from that

them to be catapulted off the flight deck.

is 260 km/hour, so let me write this down.

So your initial velocity is going to be 0,

and once again I'm going to use the convention

that the direction of the vector is implicit.

Positive means going in the direction of take-off,

My initial velocity is 0, I'll denote it as a vector

And I want to convert everything to meters

at least for meters, so that I can use my runway length

in meters. So let's just do it in meters per second,

I have a feeling it'll be a little bit easier

to understand when we talk about acceleration

So if we want to convert this into seconds,

we have, we'll put hours in the numerator,

1 hour, so it cancels out with this hour,

and this 1 km will cancel out with those kms

this dimensional analysis, you really should see

amount of time, and that's why we're dividing

many many more meters in that same amount

of time, and that's why we're multiplying

the hours cancel out, you have km canceling out,

gets me, I'll just round it to 72, because

So all I did here is I converted the take-off velocity,

so this is 72 m/s, this has to be the final velocity

what that acceleration could be, given that we know

the length of the runway, and we're going to assume

constant acceleration here, just to simplify things

The total displacement, I'll do that in purple,

equal to our average velocity while we're accelerating,

times the difference in time, or the amount of time

It's going to be our final velocity, plus our initial velocity,

over 2. It's just the average of the initial and final.

And we can only do that because we are dealing

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航母起飛的加速度｜一維運動｜物理學｜可汗學院 (Acceleration of aircraft carrier take-off | One-dimensional motion | Physics | Khan Academy)

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