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)
Answer:
q = 3.6 10⁵ C
Explanation:
To solve this exercise, let's use one of the consequences of Gauss's law, that all the charge on a body can be considered at its center, therefore we calculate the electric field on the surface of a sphere with the radius of the Earth
r = 6 , 37 106 m
E = k q / r²
q = E r² / k
q =
q = 4.5 10⁵ C
Now let's calculate the charge on the planet with E = 222 N / c and radius
r = 0.6 r_ Earth
r = 0.6 6.37 10⁶ = 3.822 10⁶ m
E = k q / r²
q = E r² / k
q =
q = 3.6 10⁵ C
In thermodynamics, entropy (symbolized as S) is a physical magnitude for a thermodynamic system in equilibrium. It measures the number of microstates compatible with the equilibrium macrostate, it can also be said that it is the reason for an increase between internal energy versus an increase in system temperature.
The universe tends to distribute energy evenly; that is, to maximize entropy. Intuitively, entropy is a physical quantity that, by calculation, allows us to determine the part of energy per unit of temperature that cannot be used to produce work.
Therefore the correct answer is B.
Answer:
- 3 cm
Explanation:
From the mirror formula;
1/f = 1/v + 1/u ; where f is the focal length, v is the image distance, and u is the object distance.
1/-4.5 = 1/9 + 1/v
1/v = -1/4.5 - 1/9
= -1/3
Therefore;
v = -3 cm
Hence;
Image distance is - 3cm
Answer:
m = 105.37 kg
Explanation:
We are given;
Mass of man; m = 113 kg
Length of boat = 6.3m
Now, The position of the center of mass will not change during the motion of the man.
Thus,
X_g,i = X_g,f
So,
[113(6.3) + ma]/(113 + m) = [113(3.26) + m(a +3.26)]/(113 + m)
113 + m will cancel on both sides to give;
113(6.3) + ma = [113(3.26) + m(a +3.26)]
711.9 + ma = 368.38 + ma + 3.26m
ma will cancel out to give;
711.9 - 368.38 = 3.26m
343.52/3.26 = m
m = 105.37 kg