When a man travels from a hilly region to the Terai region, his weight will slightly increase. This is because weight depends on gravitational force, which is inversely proportional to the square of the Earth's radius.

\(\rm g\) \(\rm ∝\) $\frac{1}{r^{2}}$

In the Terai, closer to sea level, the radius from the Earth's center is slightly smaller than in hilly areas. As a result, gravitational force is a bit stronger, making his weight slightly higher.