Basically the given explanation will make sense!

In fact, P = VI

In which,

P is the power in watt

V is the potential Difference in volt

I is the current in ampere

Now second Formula says that,

P = I

In this equation, Joule's law has combined with Ohm's law and the value of I has put in it because I = V/R. In the first equation, I and V are product and equals to power while in the second equation just the value of I has been put.

Now in the first case when Voltage will increase I will go down and in the second case the value of resistance will increase and again make the ratio of V/R equal to I in the first equation and it will not make any difference.

In fact, P = VI

In which,

P is the power in watt

V is the potential Difference in volt

I is the current in ampere

Now second Formula says that,

P = I

^{2}R = V^{2}/R = V(V/R)In this equation, Joule's law has combined with Ohm's law and the value of I has put in it because I = V/R. In the first equation, I and V are product and equals to power while in the second equation just the value of I has been put.

Now in the first case when Voltage will increase I will go down and in the second case the value of resistance will increase and again make the ratio of V/R equal to I in the first equation and it will not make any difference.