Anyone good at physics?

[skjl47]

Hello; A 2kg pendulum hanging at the end of a 2m chain has potential energy equal to zero. I swing the pendulum through 90 degrees, and hold it. What is the potential energy at 90 degrees?

At 90 degrees the pendulum bob is raised 2m above its resting point. You have moued a mass of 2 kg up 2m. I believe the formula you will need is V = m g h where V = potential g = acceleration of gravity h = vertical distance

 

[SePPii]

I understand what your saying
I think but isn't there a formula to figure it out?


Sent from my iPhone using MonsterAquariaNetwork app

 

[skjl47]

Hello; Then the next question asks me how much work does it take to reach the new potential energy?

work = force times distance W = F d where W = work F = force d= distance

 

[SePPii]

Ok well, that would make it V= 2kg(g)(2m). What is G is this situation then? Sorry I feel so dumb but it's completely new to me


Sent from my iPhone using MonsterAquariaNetwork app

 

[tomomothy]

if you mean g, g is the gravitational constant on earth, and always = 9.8m/s^2 towards earth

 

[skjl47]

Hello; g can also be 32 feet per second per second if you are not using metric units.

 

[Zfishies]

Thanks for NOT encouraging me to take physics... still have to tho seems interesting tho. Good luck see u on live lol

Sent from my GT-N7100 using MonsterAquariaNetwork App

 

[Inglorious]

Thanks for NOT encouraging me to take physics... still have to tho seems interesting tho. Good luck see u on live lol

Sent from my GT-N7100 using MonsterAquariaNetwork App

Physics is actuall pretty easy, although this thread has reminded me of how much I have forgotten in the last decade though.

 

[tomomothy]

Physics is actuall pretty easy, although this thread has reminded me of how much I have forgotten in the last decade though.

Never heard anybody call physics easy before but Im glad it was for you. I always found myself screwing up the math on longer problems and it was always the simple algebra I had been doing for years already.

Sent from the mars rover

 

[lipadj46]

Physics is easy especially high school physics. I teach it and it is frustrating when kids don't get it because they are not good at basic math. They usually make it up with their enthusiasm though as physics can be fun too

sent from my TI85 during chemistry class