find the pecentage decease in the weight of the body when it is taken 16 km below the surface of earth

We have, d = 16 km

R = 6400 km

Now, variation of ‘g’ with depth is given by,

g^/ = g (1 – d/R)

=> g^/ = g(1 – 16/6400)

=> g^/ = g(1 – 1/400)

=> g^/ = 0.9975g

=> g^//g = 0.9975

=> 1 - g^//g = 1- 0.9975

=> (g – g^/)/g = 0.0025

=> (g – g^/)/g × 100= (0.0025 × 100)% = 0.25%