Thread: Vectors

t seconds after a certain projectile is launched from the ground, it has a vertical upwards velocity component of 69.0 - 9.80t m/s. Given that is has a constant horizontal velocity component of 15.0m/s, find it's velocity (i.e its speed and direction of motion): 2 seconds after launch and 7 seconds after launch. (state direction as angles made with horizontal)

Please help with the answer!!!

Originally Posted by kingtim04

t seconds after a certain projectile is launched from the ground, it has a vertical upwards velocity component of 69.0 - 9.80t m/s.

?? You mean the initial vertical velocity is 69.0 m/s and the vertical acceleration is -9.8 m/s^2 don't you?

Given that is has a constant horizontal velocity component of 15.0m/s, find it's velocity (i.e its speed and direction of motion): 2 seconds after launch and 7 seconds after launch. (state direction as angles made with horizontal)

Please help with the answer!!!

If acceleration is a constant, a, then the speed after time t is at+ initial speed. Of course, for horizontal motion, the acceleration is 0 so the horizontal speed remains constant.