Question

The earth moves round the sun in a near circular orbit of radius $1.8\times 10^{11}m$. Its centripetal acceleration is:

• A. $6\times 10^{3}m/s^2$
• B. $10\times 10^{3}m/s^2$
• C. $12\times 10^{3}m/s^2$
• D. $10^{-3}m/s^2$

Answer 1

Answer: (A)

Centripetal acceleration, $a_c={\omega }^{2}R$
$=\frac{(2\pi {)}^2\times R}{T^2}=\frac{4\times (3.14{)}^2\times 1.8\times 10^{11}}{(365\times 24\times 60\times 60{)}^2}$
$=\frac{4\times 10\times 1.8\times 10^{11}}{{\left(31536\times 10^3\right)}^2}$
$=6\times 10^{-3}m/s^2$