10.2 Review #1

Choose INCORRECT description about satellite orbiting a planet.

• E Total = Ek + Ep

• $Ep=\frac{GMm}{r}$
  

• $\frac{GMm}{r^2}=m\ \frac{v^2}{r}$
  

• $Ep=-\ \frac{GMm}{r}$

Choose INCORRECT description about satellite orbiting a planet.

• E Total = Ek – Ep

• $v_{esc}=\sqrt{\frac{Gm}{r}}$
  

• $\frac{GMm}{r^2}=m\ \frac{v^2}{r}$
  

• $Ep=-\ \frac{GMm}{r}$

Choose INCORRECT description about satellite orbiting a planet.

• E Total = Ek + Ep

• $v_{esc}=\sqrt{\frac{Gm}{r}}$
  

• $Ek=\frac{1}{2}m\left(\frac{GM}{r}\right)=\frac{GMm}{2r}$
  

• $Ep=\ \frac{GMm}{r}$

Choose INCORRECT description about satellite orbiting a planet.

• $E_T=\frac{GMm}{2r}-\frac{GMm}{r}=-\frac{GMm}{2r}$
  

• $E_T=\frac{GMm}{2r}+\frac{GMm}{r}=\frac{3GMm}{2r}$
  

• $Ek=\frac{1}{2}m\left(\frac{GM}{r}\right)=\frac{GMm}{2r}$
  

• $Ep=\ -\frac{GMm}{r}$

Choose what is correct by launching an object into space (without rockets).

E_T = 1/2 m v² (at the site of the launch)

Find the equivalent for total of energy used in the launch.

• E_T = – GMm / 2r

• E_T = GMm / 2r

• E_T = – GMm / r

Choose what is correct by launching an object into space (without rockets).

E_T = Ek + Ep = zero

• Projectile will take a circle or ellipse orbital path A. (maybe not enough speed)

• Projectile will take a parabola orbital path B.

• Projectile will take a hyperbola orbital path C.

Choose what is correct by launching an object into space (without rockets).

E_T = Ek + Ep > zero (positive magnitude)

• Projectile will take a circle or ellipse orbital path A. (maybe not enough speed)

• Projectile will take a parabola orbital path B.

• Projectile will take a hyperbola orbital path C.

Choose what is correct by launching an object into space (without rockets).

E_T = Ek + Ep < zero (negative magnitude)

• Projectile will take a circle or ellipse orbital path A. (maybe not enough speed)

• Projectile will take a parabola orbital path B.

• Projectile will take a hyperbola orbital path C.

Center of planet is at r=0, center of its moon is at r=1.0

Find the potential at the point where there is no gravity between this planet and its moon.

• r=0.84 and V_g = -0.4x10⁸ J/kg

• r=0.04 and V_g = -3.9x10⁸ J/kg

• r=0.99 and V_g = -3.9x10⁸ J/kg

• r=0.5 and V_g = -0.6x10⁸ J/kg

Choose the INCORRECT description.
Projectile with mass m reaches x position and become at rest.

•  $v_{esc}=\sqrt{\frac{2GM_{planet}}{R_{planet}}}$  

•  $E_{T\ at\ Launch}=\frac{1}{2}mv_{esc}^2-\frac{GMm}{R_{planet}}$  

•  $E_{T\ at\ x}=zero$  

•  $E_{T\ at\ x}=-\frac{GMm}{R_{planet}}$