A satellite of mass 150 KG launched 3000km above the earths surface What is the speed?
Q. A satellite of mass 150kg is launched 3000km above the earths surface. A. What is the speed of the satellite in its orbit? B. What is providing the centripetal force on it? What is its value? C. What is the time period of the satellite?
Asked by John Q - Thu Oct 25 23:54:22 2007 - - 1 Answers - 0 Comments

A. Please capitalize Earth. It's a proper noun, just like London or Mexico. It's not clear in this problem how many significant digits of accuracy we are dealing with, but 3 digits would be generous. We should keep at least 5 digits during our calculations and then round off our answers to 3 digits. At 3000km above Earth's surface, the satellite is 9370km from the center of the Earth. Its weight at that height is 150*9.80*(6370/9370)^2 = 679.387 Newtons. This is the centripetal force, the force of gravity. Now we can use F = mv^2/r to find the orbital velocity. F = m * v^2 / r note: we need the radius in meters, not km 679.387 = 150 * v^2 / 937000 42439042 = v^2 6514.5 = v This is the orbital velocity in meters per second. The total length… [cont.]
Answered by dogwood_lock - Sun Oct 28 03:09:03 2007

How can I get Outlook to check my mail automatically when it's launched?
Q. I have Outlook 2007 running on Vista. When I launch Outlook, it doesn't automatically do a send/receive. I have it set to send/receive every five minutes. Is there a way to make it do a send/receive automatically when Outlook is launched?
Asked by David M - Wed Jan 7 11:32:37 2009 - - 2 Answers - 0 Comments

A. Change how often a POP3 account sends mail and checks for new items ( Source = ) For POP3 e-mail accounts, you can specify how often to check for new items. On the Tools menu, point to Send/Receive, point to Send/Receive Settings, and then click Define Send/Receive Groups. (Keyboard shortcut To open the Send/Receive Groups dialog box, press CTRL+ALT+S). Select the Send/Receive group that contains the POP3 e-mail account that you want to change. Under Setting for group send/receive group name, select the Schedule an automatic send/receive every n minutes check box. Enter a number between 1 and 1440. The latter will schedule an automatic send/receive once daily. Note: When you change the schedule for a Send/Receive group, all… [cont.]
Answered by Quantum Dragon - Wed Jan 7 13:05:51 2009

. A rocket ascends vertically after being launched from a location that is midway between two ground?
Q. Skill IVB2. A rocket ascends vertically after being launched from a location that is midway between two ground-based tracking stations. When the rocket reaches an altitude of 12 kilometers it is 13 kilometers from each of the tracking stations. How far apart are the two tracking stations? Assume that this is a locale where the terrain is flat.
Asked by kris h - Thu Nov 27 19:15:05 2008 - - 3 Answers - 0 Comments

A. 10 km you draw a horizontal base line across the middle of a page to represent the ground then draw a vertical line up from around the centre to represent the trajectory of the rocket (mark this line 12 km) then mark roughly where the tracking stations might be - either side of the rocket (don't worry about accuracy). join up the top of the trajectory line with these two points. mark each one 13 km you now have two right angled triangles now use pythagoras's thereom (h^2 = a^2 + b^2, where h stands for the hypotenuse - the side opposite the right angle, and a and b stand for the other two sides, so; h^2 =a^2 + b^2 13^2 = 12^2 + b^2 169 = 144 + b^2 169 - 144 = b^2 b^2 = 25 b = the square root of 25 = 5 so it's 5 km from the… [cont.]
Answered by cliff - Thu Nov 27 19:41:53 2008