When it is 152 m above the ground, a rocket traveling vertically upward at a constant 9.50 m/s relative to the ground launches a secondary rocket at a speed of 12.4 m/s at an angle of 50.0 degrees above the horizontal, both quantities being measured by an observer sitting in the rocket. Air resistance should be ignored.

Just as the secondary rocket is launched, what are the horizontal and vertical components of its velocity relative to Mission Control on the ground?

1 answer

well, if the 12.4m/s per second was measured by a ground observer, then that is the actual velocity.
vertical: 12.4sin50
horizontal: 12.4cos50

Normally, I would have assumed the 12.4m/s was relative to the launching rocket, so that the actual velocity would be added to the rocket. Such is life.