Question #07b7f

1 Answer
Mar 24, 2016

See steps below.

Explanation:

(a) Given expression is V=V_0cdote^(-t/(RcdotC))V=V0etRC
To make tt its subject.
Divide both sides with V_0V0 and take natural logarithm of both sides.
In the first step we obtain
V/V_0=e^(-t/(RcdotC))VV0=etRC
In the second step
ln (V/V_0)=ln e^(-t/(RcdotC))ln(VV0)=lnetRC, eliminating ee
ln (V/V_0)=-t/(RcdotC)ln(VV0)=tRC, now making tt its subject
t=-(RcdotC)cdotln (V/V_0)t=(RC)ln(VV0), absorbing -ve " sign in " lnve sign in ln function
t=RcdotCcdotln (V_0/V)t=RCln(V0V).

(b) For the second part follow same steps as above to obtain
t=lambdacdotln (N_0/N)t=λln(N0N)