The diagonal of a square equals the square root of 2 times the side length. Using 1.4 for the square root of 2, what is the approximate length in inches from one corner to an opposite corner of the square that is 650 feet on a side?

To find the length of the diagonal of a square, we can use the relationship that the diagonal \( d \) is given by:

\[
d = s \cdot \sqrt{2}
\]

where \( s \) is the side length of the square. In this case, the side length \( s \) is given as 650 feet, and we will use the approximation \( \sqrt{2} \approx 1.4 \).

Substituting the values into the formula for the diagonal, we have:

\[
d = 650 \cdot 1.4
\]

Calculating this:

\[
d = 650 \cdot 1.4 = 910 \text{ feet}
\]

Now, we need to convert the diagonal length from feet to inches. We know that there are 12 inches in a foot, so we can do the conversion as follows:

\[
d_{\text{inches}} = d_{\text{feet}} \cdot 12 = 910 \cdot 12
\]

Calculating this gives:

\[
d_{\text{inches}} = 10920 \text{ inches}
\]

Thus, the approximate length from one corner to the opposite corner of the square is:

\[
\boxed{10920} \text{ inches}
\]