Question

please explain the question correctly class 11th​

Answer 1

✪GIVEN :-. Distance travelled by stone =24.5 in last second.

✪TO FIND :-. Height of the tower .

✪FORMULAS USED :-

$= > s = ut + \frac{1}{2} at {}^{2}$

$= > h = \frac{1}{2} gt {}^{2}$

✍️ SOLUTION :-

Let the height of tower =h.

$= > sn = u + \frac{1}{2} a(2n - 1)$

$= > 24.5 = 0 + \frac{10}{2} (2n - 1)$

$= > 24.5 = 5(2n - 1)$

$= > 24.5 = 10n - 5$

$= > 19.5 = 10n$

$= > 1.95 = n$

So, Distance travelled in last second is 1.95.

And, Distance travelled in (n-1)th second

$= > sn = u + \frac{1}{2} g(2n - 1)$

$= > 24.5 = 5(2(n - 1) - 1)$

$= 5(2n - 3)$

$= 10n - 15$

$24.5 = 10n - 5$

$= > 0.95$

Total time taken = 1.95 + 0.95 = 2.9sec.

=> Height = 1/2 gt^2

=5(2.9)^2.

= 42.5m .

$\boxed{HENCE, HEIGHT \: OF \: TOWER \: \: = 42.5 }$

HOPE IT HELPS :)