What is the period (in hours) of a satellite circling Mars 100 km ...

[PhilipSeeMore]

What is the period (in hours) of a satellite circling Mars 100 km above the planet's surface?
 
  The mass of Mars is 6.42  1023 kg, its radius is 3.40  106 m, and G = 6.67  10-11 N  m2/kg2.
  A) 1.45 h B) 1.00 h C) 1.15 h D) 1.25 h E) 1.75 h

Question 2

An alpha particle is a nucleus of helium. It has twice the charge and four times the mass of the proton. When they were very far away from each other,
 
  but headed toward directly each other, a proton and an alpha particle each had an initial speed of 0.0030c, where c is the speed of light. What is their distance of closest approach? Hint: There are two conserved quantities. Make use of both of them. (c = 3.00  108 m/s, k = 1/40 = 8.99  109 N  m2/C2, e = 1.60  10-19 C, mproton = 1.67 x 10-27 kg)
  A) 3.3  10-13 m B) 2.6  10-13 m C) 2.1  10-13 m D) 2.9  10-13 m

[iman]

Answer to Question 1

E

Answer to Question 2

C

[PhilipSeeMore]

Wow, this really help

[Animal_Goddess]

Thanks for the timely response, appreciate it