Most popular questions and responses by Physics PLEASE

I'm trying to solve this problem Calculate (a) how long it took King Kong to fall straight down form the top of the Empire State Building (380 m high), and (b) his velocity just before "landing". My teacher said try and rearagne this equation for t X = Xo

You want to show that V^2 - Vo^2 = 2 a (X - Xo) first rewrite that as: (V-Vo)(V+Vo) = 2a (X-Xo) now your average velocity during the interval = (V+Vo)/2 so X = Xo + t(V+Vo)/2 but V = Vo + a t so t = (V-Vo)/a so X = Xo +(V-Vo)(V+Vo)/2a we are there.

I'm trying to derive the formula v^2 = v0^2 + 2a(x-x0) were zeros are subscripts my book tells me to derive it this way use the definition of average velocity to derive a formula for x use the formula for average velocity when constant acceleration is

I'm trying to solve this problem Calculate (a) how long it took King Kong to fall straight down form the top of the Empire State Building (380 m high), and (b) his velocity just before "landing". My teacher said try and rearagne this equation for t X = Xo

Of course you have to rearrange it X -Xo = (V-Vo)(V+Vo)/2a (X-Xo)2a = (V-Vo)(V+Vo) 2 a (X-Xo) = V^2-Vo^2 ok to go from the first line to the second line you multiply by 2a I agree but what allows you to just put parenthsess around the X-Xo Thank You!

oh... Xo is not zero

posted on June 23, 2009