Answer: ![-\frac{1}{2}\times \frac{d[Br^.]}{dt}=+\frac{d[Br_2]}{dt}](https://tex.z-dn.net/?f=-%5Cfrac%7B1%7D%7B2%7D%5Ctimes%20%5Cfrac%7Bd%5BBr%5E.%5D%7D%7Bdt%7D%3D%2B%5Cfrac%7Bd%5BBr_2%5D%7D%7Bdt%7D)
Explanation:
Rate of a reaction is defined as the rate of change of concentration per unit time.
Thus for reaction:

The rate in terms of reactants is given as negative as the concentration of reactants is decreasing with time whereas the rate in terms of products is given as positive as the concentration of products is increasing with time.
![Rate=-\frac{d[Br^.]}{2dt}](https://tex.z-dn.net/?f=Rate%3D-%5Cfrac%7Bd%5BBr%5E.%5D%7D%7B2dt%7D)
or ![Rate=+\frac{d[Br_2]}{dt}](https://tex.z-dn.net/?f=Rate%3D%2B%5Cfrac%7Bd%5BBr_2%5D%7D%7Bdt%7D)
Thus ![-\frac{d[Br^.]}{2dt}=+\frac{d[Br_2]}{dt}](https://tex.z-dn.net/?f=-%5Cfrac%7Bd%5BBr%5E.%5D%7D%7B2dt%7D%3D%2B%5Cfrac%7Bd%5BBr_2%5D%7D%7Bdt%7D)
Explanation:
A lever is a rigid bar which moves freely about a fixed point called fulcrum....
The types of lever are :
- First class lever
- Second class lever
- Third class lever....
Answer:
0.139 rad
Explanation:
We use Snell's law
, where if
is the <em>refractive index</em> of the medium containing the <em>incident ray</em>,
would be the <em>incident angle</em>, and if
is the <em>refractive index</em> of the medium containing the <em>refracted ray</em>,
would be the <em>refraction angle</em>, which we want, so we do:

And finally:

We then insert our values:

Answer:

Explanation:
<u>Given Data:</u>
Length = l = 820 mm = 0.82 m
Acceleration due to gravity = g = 9.8 ms⁻²
<u>Required:</u>
Frequency = f = ?
<u>Formula:</u>

<u>Solution:</u>
![\displaystyle f =\frac{1}{2 \pi} \sqrt{\frac{g}{l} } \\\\Put\ the\ givens\\\\f=\frac{1}{2 \pi} \sqrt{\frac{9.8}{0.82} }\\\\ f = 0.159 \times \sqrt{11.95} \\\\f=0.159 \times 3.457\\\\f=0.55 \ Hz\\\\\rule[225]{225}{2}](https://tex.z-dn.net/?f=%5Cdisplaystyle%20f%20%3D%5Cfrac%7B1%7D%7B2%20%5Cpi%7D%20%5Csqrt%7B%5Cfrac%7Bg%7D%7Bl%7D%20%7D%20%5C%5C%5C%5CPut%5C%20the%5C%20givens%5C%5C%5C%5Cf%3D%5Cfrac%7B1%7D%7B2%20%5Cpi%7D%20%5Csqrt%7B%5Cfrac%7B9.8%7D%7B0.82%7D%20%7D%5C%5C%5C%5C%20f%20%3D%200.159%20%5Ctimes%20%5Csqrt%7B11.95%7D%20%5C%5C%5C%5Cf%3D0.159%20%5Ctimes%203.457%5C%5C%5C%5Cf%3D0.55%20%5C%20Hz%5C%5C%5C%5C%5Crule%5B225%5D%7B225%7D%7B2%7D)