Question

The percentage decrease in the weight of a rocket, when taken to a height of 32 km above the surface of earth will, be:
(Radius of earth = 6400 km)

• A. 1%
• B. 3%
• C. 4%
• D. 0.50%

Answer 1

Answer: (A)

1%

Answer 2

We know that,
$g=\frac {GM}{r^2}$
The percentage decrease in the weight of a rocket,

$⇒\frac {Δg}{g}=2\frac {Δr}{r}$

$⇒\frac {Δg}{g}×100=2×\frac {32}{6400}×100$

$⇒\frac {Δg}{g}=1$
% decrease in weight = $1$

So, the correct option is (A): $1$