Hi! I'm working on a circular motion problem, and I'm not sure on how to go about doing it. The question: A spacecraft moves in a circular orbit with a speed of 7360 m/s with a period of 6270. seconds. The radius of the spacecraft's orbit is 7.34 x 10^6 m and the radial acceleration of the satellite is 7.38 m/s^2. In order to begin its re-entry, the spacecraft engines are fired to provide an acceleration of 6.60 m/s^2 in a direction opposite to its velocity. What is the magnitude of the spacecraft's total acceleration just after the engines begin to fire? My first try at the question involved simply adding a negative 6.60 m/s^2 to the radial acceleration (7.38 m/s^2). I came up with 0.780 m/s^2 for the spacecraft's total acceleration which is wrong. If anyone could point be in the right direction on how to go about this problem it would be greatly appreciated. Thanks.