Posted by Susan on .
The infamous German "Paris gun" was used to launch a projectile with a flight time of 170 s for a horizontal distance of 122 km. Based on this information, and ignoring air resistance , calculate (a) the gun's muzzle speed and (b) the angle, measured above the horizontal, at which it was fired.

physics 
drwls,
Horizontal velocity component (a constant)
= Vx = 122,000/170 = 717.6 m/s
Vertical velocity component (initially)= Vy = g*85s = 833.0 m/s
Muzzle speed = sqrt[(717.6)^2 + (833)^2]
= 1100 m/s
Firing angle = tan^1 (833/717.6) = 49.3 degrees