Multiple Choice
Sputnik I was launched into orbit around Earth in 1957. It had a perigee (the closest approach to Earth, measured from Earth's center) of 6.81 × 106 m and an apogee (the furthest point from Earth's center) of 7.53 × 106 m. What was its speed when it was at its perigee? The mass of Earth is 5.97 × 1024 kg and G = 6.67 × 10-11 N ∙ m2/kg2.
A) 7180 m/s
B) 7840 m/s
C) 8230 m/s
D) 11,000 m/s
E) 13,400 m/s
Correct Answer:

Verified
Correct Answer:
Verified
Q2: Ekapluto is an unknown planet that has
Q4: The weight of spaceman Speff at the
Q5: A huge cannon is assembled on an
Q6: Three identical very small 50-kg masses are
Q7: From what height above the surface of
Q9: The gravitational acceleration on a planet's surface
Q11: A certain planet has an escape speed
Q22: The moons of Mars,Phobos (Fear)and Deimos (Terror),are
Q27: If the mass of the earth and
Q30: Because the earth's orbit is slightly elliptical,the