Fermi
·
Concept Library
·
Courses
·
Books
·
Problems
·
Simulations
·
Math Wiki
·
High School
Fermi
›
Problems
A comet of negligible initial speed approaches Earth from infinity along a straight line
PHYSICS · Single correct · CBSE · Physics · Gravitation · Gravitation
Problem
A comet of negligible initial speed approaches Earth from infinity along a straight line. At what distance from Earth’s centre will its speed first reach one-half of Earth’s surface escape speed? (a)
2
R
⊕
2R_{\oplus}
2
R
⊕
(b)
8
R
⊕
8R_{\oplus}
8
R
⊕
(c)
4
R
⊕
4R_{\oplus}
4
R
⊕
(d)
4
3
R
⊕
\dfrac{4}{3}R_{\oplus}
3
4
R
⊕
Related theory
Escape Velocity
Gravitation
Gravitational potential and energy
Escape speed
Browse the problem library