Question

A particle hanging from a massless spring stretches it by $2cm$ at the eath's surface. How much will the same particle stretch the spring at a height of $2624Km$ from the surface of the earth? (Radius of the earth$=6400Km$)

• A. $1cm$
• B. $2cm$
• C. $3cm$
• D. $4cm$

Answer 1

The correct option is A $1cm$

$△l\alpha F\Rightarrow △l\alpha mg\Rightarrow △l\alpha g\therefore \frac{△l_2}{△l_1}=\frac{g_2}{g_1}\Rightarrow \frac{△l_2}{2}=\frac{\frac{GM}{{(6400+2624)}^2}}{\frac{GM}{{\left(6400\right)}^2}}\Rightarrow △l_2=1$

$\therefore △l_2$ will be $1cm$.