Question

If you have a mass of 50 kg on
Earth, what is your weight in Newtons?

Answer 1

Your weight will be 50 x 10 = 500 N

Considering g = 10 m/s²

Answer 2

Weight on any planet is (mass) x (acceleration of gravity there).

Acceleration of gravity on Earth is about 9.8 meters per second² .
So weight of 50 kg on Earth is  (50 x 9.8) = 490 newtons.

(That's about  110.2 pounds.)