Question

The braking distance of a car is proportional to the square of its speed.17. According to Graham's law, the rate of diffusion of two gases is inverselydproportional to density and is given bywhere ', and r2 are12rates of diffusion of two gases and d, and d2 are their respectivedensities. Which equation represents d, in terms of the other variables?

Answer 1

Ok in this problem you have to take Graham's law which is given to you and manage to write the density d1 as a function of the others. We have:

`(r_1)/(r_2)=\sqrt[]{(d_2)/(d_1)}`

Since we want to have d1 alone in one side of the equation the first thing we have to do is pass the square root to the other side. Square roots pass as square powers:

`((r_1)/(r_2))^2=(d_2)/(d_1)`

Then we have to pass d1 multiplying on the other side:

`d_1(r^2_1)/(r^2_2)^{}=d_2`

Now we only need to pass both r1 and r2:

`d_1=d_2(r^2_2)/(r^2_1)`

This is the same expresion that the one in item B so that is the correct answer