I dont understand how to find acceleration for the second part

[Sneakatone]

for the first two I used the equation a=v^2/r
but for the second part I don't know what it is asking for or how to approach it. is there an equation that goes with it?

 

[Sneakatone]

the 1st two are wrong when I use a=v/r it is also wrong, and I converted km/h to m/s

 

[tiny-tim]

Hi Sneakatone!

a = v²/r should be correct.

How exactly did you get 74.3 and 197.7 ?

 

[HallsofIvy]

$$a= v^2/r$$ will give the acceleration due to the motion around the circle. The actual force the pilot experiences will be those plus or minus the weight of the pilot.

 

[Sneakatone]

105.5^2/150=74.2 m/s
172.22^2/150= 197.7 ms

 

[tiny-tim]

erm …

it's not 150 ! ​

 

[Sneakatone]

the diameter is 300 so 1/2 of it is 150 , that's where I got it. and then I tried using the whole diameter ans that is not right

 

[tiny-tim]

no, the diameter is 1000

 

[Sneakatone]

well sonb , I can't believe I didnt see that thanks!
now that we have that I still don't know how to do the second part.

 

[tiny-tim]

… I still don't know how to do the second part.

you mean the centripetal acceleration at the bottom?

same method ​

 

[Sneakatone]

would i use gravity and the magnitude?

 

[tiny-tim]

do you mean the third part?

yes, you have to take gravity into account

 

[Sneakatone]

Im thinking it would be something like 22.1-(1/2*9.82) because gravity is downward on a horizontal acceleration.?

 

[tiny-tim]

you're doing it again!

where do those figures come from? ​

 

[Sneakatone]

the way I am thinkg of it is that the found acceleration which is 22.1 is being acted upon a down ward acceleration of gravity.

how would you do this?

 

[tiny-tim]

(i don't make it exactly 22.1)

where did the 1/2 come from?

has your professor taught you about rotating frames of reference, and centrifugal force? what do you know about them?

(i'm off to bed now :zzz:)

 

[Sneakatone]

I believe not , i don't even know which equation I should appy

 

[Sneakatone]

I believe not , I ont even know which equaton to apply.
it seems like w^2r is a possibility.

 

[tiny-tim]

(just got up :zzz:)

has your professor taught you about rotating frames of reference, and centrifugal force? what do you know about them?

(ω²r and v²/r are the same, since v = ωr, even when ω isn't constant)