Question

A satellite of mass m moves around the earth in a circular orbit with speed v. The potential energy of the satellite is –

• A. mv²
• B. – mv²
• C. $\frac { 3 } { 2 }$ mv²
• D. – \frac { 3 } { 2 } mv²

Answer 1

Answer: (B)

– mv²

Answer 2

U = – $\frac { \mathrm { GMm } } { \mathrm { r } }$ , kinetic energy =

U = (–2) $\frac { \mathrm { GMm } } { 2 \mathrm { r } }$ = –2 × kinetic energy

= –2 × $\frac { 1 } { 2 }$mv² = – mv²