Question

Equipotential surfaces are

• A. Surfaces that are perpendicular to gravitational fields
• B. Surfaces that have same mass on top of it
• C. Surface that have same radius of curvature
• D. Surfaces that have same gravitational field on it

Answer 1

Answer: (A)

Surfaces that are perpendicular to gravitational fields

• Equipotential surfaces are surfaces which have the same value of potential throughout their surface.
  
• For a gravitatiomal field of $E=\frac{GM}{r^2}$,the potential is $v=-\frac{GM}{r}$
• So,at a particular 'r',the potential remains constant at a value of $-\frac{GM}{r}$
• So equipotential surfaces are circles for the filed of $E=\frac{GM}{r^2}$
• Hence,the field is perpendicular to equipotential surface.