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# physics..Oscillations...problemm m..!! watch

A mass on the end of a light helical spring is given a vertical displacement of 3.0 CM from its rest position and then released. If the subsequent motion is simple harmonic with a period of 2.0 Second, through what distance will be bob move in

a) The first 1.0 second

b) The first 0.75 second

ANSWER ACCORDING TO BOOKLET (a) 6.0 CM
(b) 5.1 CM

PLEASE SHOW THE EQUATION THAT YOU ARE USING...THANKS...!!!!!!
2. x = A cos(wt) (cos because it's moving vertically, it seems.)

w = omega = 2pi·f = 2pi/T = 2pi/2 = pi (because f = 1/T)
A = 3 x 2 = 6 (double because the initial displacement was only in 1 direction, down)

Put each time in, to get x.

Why isn't it working?

I should go to bed.
3. (Original post by + polarity -)
x = A cos(wt) (cos because it's moving vertically, it seems.)

w = omega = 2pi·f = 2pi/T = 2pi/2 = pi (because f = 1/T)
A = 3 x 2 = 6 (double because the initial displacement was only in 1 direction, down)

Put each time in, to get x.

Why isn't it working?

I should go to bed.

BECAUSE:

S = a cos ( 2(pie) f t )

replacing these unknown where w(omega) is pie,, and t = 1 leave us with cos pie which is equal to -1 ..?? so ...!!!!!

I do not really understand what you have done...PLEASE CAN YOU REEXPLAIN IT TO ME BY MAKING USE OF THE FORMULA AND REPLACE IT IN THE EQUATION....

BY THE WAY I THINK THAT IN ORDER TO CONFIRM WHETHER YOUR ANSWER IS CORRECT YOU MUST DO THE SECOND PART THAT IS ( b ) WHERE YOU CAN CONFIRM...!!!!!!
4. (Original post by jinx007)

A mass on the end of a light helical spring is given a vertical displacement of 3.0 CM from its rest position and then released. If the subsequent motion is simple harmonic with a period of 2.0 Second, through what distance will be bob move in

a) The first 1.0 second

b) The first 0.75 second

ANSWER ACCORDING TO BOOKLET (a) 6.0 CM
(b) 5.1 CM

PLEASE SHOW THE EQUATION THAT YOU ARE USING...THANKS...!!!!!!
idk what spec you doin but just use: x= Asinwt
where w= angular Velocity.
so here from the info given:Amplitude = 3x10-2m
W= 2Pie/T (T=2 second)
so W= pie
therefore: (3x10^-2)sin(pie) = 0 o.0 wth

its weird i think i did Write, tbh the question sounds prettY straight forward maybe The booklet is wrong?
5. (Original post by jinx007)

A mass on the end of a light helical spring is given a vertical displacement of 3.0 CM from its rest position and then released. If the subsequent motion is simple harmonic with a period of 2.0 Second, through what distance will be bob move in

a) The first 1.0 second

b) The first 0.75 second

ANSWER ACCORDING TO BOOKLET (a) 6.0 CM
(b) 5.1 CM

PLEASE SHOW THE EQUATION THAT YOU ARE USING...THANKS...!!!!!!
ermm did you try velocity equation? maybe you need to find out its velocity then divide it over time to get displacement?
6. (Original post by ibysaiyan)
idk what spec you doin but just use: x= Asinwt
where w= angular Velocity.
so here from the info given:Amplitude = 3x10-2m
W= 2Pie/T (T=2 second)
so W= pie
therefore: (3x10^-2)sin(pie) = 0 o.0 wth

its weird i think i did Write, tbh the question sounds prettY straight forward maybe The booklet is wrong?

Awww do you think so.. I DON'T REALLY... BECAUSE I THINK ITS A DEMANDING QUESTION..MIND PUZZLING..??? BECAUSE THE QUESTION CARRIES 3 MARK EACH SO I DO NOT THINK YOU WILL GET 3 MARK FOR A STRAIGHT FORWARD QUESTION.. I THINK THE ANSWER OF THE BOOKLET IS CORRECT...!!!!!!!!!!!!!!
7. 1 mark for equation, 1 mark for correct subtitute informations and 1 mark for answer
normally like dat
8. (Original post by jinx007)

A mass on the end of a light helical spring is given a vertical displacement of 3.0 CM from its rest position and then released. If the subsequent motion is simple harmonic with a period of 2.0 Second, through what distance will be bob move in

a) The first 1.0 second

b) The first 0.75 second

ANSWER ACCORDING TO BOOKLET (a) 6.0 CM
(b) 5.1 CM

PLEASE SHOW THE EQUATION THAT YOU ARE USING...THANKS...!!!!!!
Period of oscillation is defined as the time taken to complete one full cycle (ie: bounce up to the maximum height, then return to the starting displacement). In 1 second = half the period, it'll evidently travel half the full oscillation, ie: up to the top. That gives distance travelled = 2(3) = 6 cm. By equations:

at t = 1

Distance from 3 cm to -3 cm is 6 cm. Voila.

Same principle for part (b).

EDIT:
(Displacement is a vector, so a negative answer just means an upward displacement from the rest position rather than a downwards one. )

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