Question

for the simple harmonic motion equation d=1.3cos(((3π)/4)t), find the frequency and length of the pendulum

Answer 1

i'm not sure. But the formula look like d=1.3cos(wt). So w=2pi*frequency

Answer 2

then, T (period)=1/f and then T=2pi*root(length/gravity)

Answer 3

so what would the answer be from there and how would i find it

Answer 4

substitue constants

Answer 5

to formula

Answer 6

what are the constants?

Answer 7

it is the equation

Answer 8

to that formula? T=2pi*root(length/gravity)

Answer 9

so what would the formula be after i substituted

Answer 10

d=1.3cos(((3π)/4)t) => (3π)/4=w => w=2πf => f=w/2π

Answer 11

f=1/T => T=2π*root(l/g)

Answer 12

ok?

Answer 13

thanks

Answer 14

T=2π*root(l/g) formula of pendulum, frequency is always inverse to period so f=1/T

Answer 15

what does t equal then can we find it from there or is there not enough info

Answer 16

it is not given, we dont need it. time required to solve equation at a specific time

Answer 17

oh i see, so what is the final answer then?

Answer 18

solve it yourself, just substitute the numbers and you got frequency, length of pendulum

Answer 19

im so confused. so solve this? T=2π*root(l/g) how do i know what l, g, and root are?

Answer 20

\[T=2π\sqrt{\frac{ L }{ G }}\]

Answer 21

L - Length of pendulum
G - gravity (9.8m/s^2)

Answer 22

ohh thank you

Answer 23

but i dont know what t equals so how do i solve for l then

Answer 24

what is "I" ?

Answer 25

L

Answer 26

you DO NOT need t. d=1.3cos(w*t)

Answer 27

3pi over 4 is "w"

Answer 28

are you kidding me?

Answer 29

ok thanks. its hard to learn this over the internet. u dont have to be rude.

Answer 30

sorry))

Answer 31

its ok. so then d=1.3cos(135t) right