1. Vibration of an object about an equilibrium point is called simple harmonic motion when the restoring
force is proportional to

Question

1. Vibration of an object about an equilibrium point is called simple harmonic motion when the restoring
force is proportional to

roadjester · Answer

F=ma
F=-kx
-kx=ma
a= -(k/m) x

raffle_snaffle · Answer

^What he said...

anonymous · Answer

my answer choises are

time 
displacement
a spring constant 
mass

raffle_snaffle · Answer

why mass?

roadjester · Answer

spring constant
@raffle_snaffle my bad

raffle_snaffle · Answer

Ahh lol

raffle_snaffle · Answer

You were scaring me there for a sec

anonymous · Answer

can yall help me with 6 more questions?

roadjester · Answer

F_s is the restoring force and F=ma so I just said mass

roadjester · Answer

sure thing

anonymous · Answer

2. By what factor should the length of a simple pendulum be changed in order to triple the period of
vibration?

anonymous · Answer

3
6
9
27

roadjester · Answer

one sec, I need to do some quick math

raffle_snaffle · Answer

T = 2π√(L/g)

raffle_snaffle · Answer

Solve for L

roadjester · Answer

ok, what he said

roadjester · Answer

lol

anonymous · Answer

6??

roadjester · Answer

nope

raffle_snaffle · Answer

How did you get 6?

raffle_snaffle · Answer

Can I seeyour calculations?

anonymous · Answer

im not sure how to do it thats what my calculator got

raffle_snaffle · Answer

You might have plugged it in the calculator wrong.

anonymous · Answer

how do i plug it in? sorry im horrible at physics

roadjester · Answer

this isn't physics anymore, it's math

roadjester · Answer

and you're not supposed to plug it in, you're supposed to use a ratio

roadjester · Answer

you have T1 and T2 where T2=3T1
so if you write it as a fraction 
T2/T1 using the period equation that @raffle_snaffle wrote
 you'll get your answer

roadjester · Answer

did that help at all?

anonymous · Answer

well ive narrowed it down to 3 or 9 but im leaning twords 9

roadjester · Answer

correct

roadjester · Answer

good job

roadjester · Answer

uhh I think I may need to see the picture

anonymous · Answer

sorry i posted the wrong question

roadjester · Answer

actually, i'll be back, maybe 15 min

anonymous · Answer

4. The superposition of mechanical waves can be observed in the movement of 


bumper cars
water waves in a ripple
electromagnetic radiation
violin bows in an orchestra

anonymous · Answer

Hold it: did you end up concluding as you should that the restoring force needs to be proportional to the DISPLACEMENT?

raffle_snaffle · Answer

I don't think so. I thought it was K

raffle_snaffle · Answer

the constant K?

anonymous · Answer

Pendulum: period proportional to sqrt(L/g) so to get it 3x longer in time need  L to be 9x longer in length.

raffle_snaffle · Answer

Thanks