goIIT: IIT JEE AIEEE CET WBJEE VITJEE BITSAT IIIT AICET Engineering Entrance Experts, Student Discussion Community, IIT JEE Preparation Online

w = w_o-

. t

(w - w_o) and 't' are given..
find alpha
and substitute in
I.

=

here I = 2/5 MR²
solve for torque (tau)

no.. i think that was slightly diferent.. that had equilateral triangles and all i think

edited.. horrific error!

edited.. extremely sorry..

thx compute..

by rectangular block, u mean cuboid?

edit.. complete stupidity..

thx madness

it doesnt imply anything. this is just a combination of associative law and commutative law for dot droduct of vectors, which is ALWAYS true..

so a,b,c can be any 3 vectors..

congrats anchit!! u deserve it!

last qsn i'm gettin a,b,c are in HP.. after that im not sure what to do..

theres a typo in that qsn..
is the ans comin for s = a + b + c + d??

arent those 2 compunds formed only in the case of NaOH + oxide of Al or Zn.. and not just Al or Zn??

dont be so rude computer001 :D

1.
$\sum_{i=1}^{n} \frac 1 {\frac {r(r+1)}{2}}$

$= 2. \sum_{i=1}^{n} \frac 1{r(r+1)}$

$= 2. \sum_{i=1}^{n} \frac {(r+1) - r }{r(r+1)}$

$= 2. [\sum_{i=1}^{n} \frac 1 {r} - \sum_{i=1}^{n} \frac 1 {r+1}]$

$= 2[ (\frac 1 1 - \frac 1 2) + (\frac 1 2 - \frac 1 3) ....... + (\frac 1 n - \frac 1 {n+1})]$

everything except the first and last term gets cancelled

$= 2 ( 1 - \frac 1 {n+1})$

$= \frac {2n}{n+1}$

Smile

sorry for the late reply mate.. had logged off
anyway, here's the image.. hope its useful :)
click on it to enlarge..

draw the projection of the point at any instant on the x axis..
the distance of the projection from the point will be = R cos

but theta is nothing but

* t
so, position will be = R cos (omega*t)

which is sinusoidal in nature