Answer to Question #237428 in Mechanics | Relativity for Emmyberry

Question

An object is shot from the ground into the air. Right at a speed of 50 m/s and an angle of 60 degrees above the horizontal it explodes. One fragment leaves the object to the left at a speed of 75 m/s and an angle of 45 degrees below the horizontal. What is the velocity of the fragment with respect to the ground?

Answer 1

Answer

• When the air resistance is neglected the explosion takes place in a way the linear momentum is conserved.
• In addition, the locus of the center of mass remains in the originally meant trajectory while the fragments define their own trajectories just after the explosion.
• So, just after the explosion, the effects of the previous motion could be neglected & the said velocity of the fragment could be taken as it is.

• Therefore, (if the object was originally shot to the right,) the velocity of the given fragment is $\small \bold{75\,ms^{-1}\,[S \,45\,W]}$ or 75 m/s, 45 degrees South of West