Projectile and conservation of motion

AI Thread Summary
A projectile with a mass of 6 kg is launched at 74 m/s and 20 degrees, exploding into two fragments at the peak of its trajectory. The 2.3 kg fragment lands directly below the explosion point 4.4 seconds later, while the task involves calculating the velocity of the 3.7 kg fragment immediately after the explosion, the distance it travels before hitting the ground, and the energy released during the explosion. The user is attempting to find the velocity of the 3.7 kg fragment using conservation of momentum but is struggling with separating the components of velocity. The discussion highlights the need for clarity in calculating both the x and y components of motion to solve the problem correctly. Understanding the conservation of momentum and energy principles is essential for accurate calculations in projectile motion scenarios.
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A projectile of mass 6 kg is fired with an
initial speed of 74 m/s at an angle of 20 degrees with
the horizontal. At the top of its trajectory,
the projectile explodes into two fragments of
masses 3.7 kg and 2.3 kg . The 2.3 kg fragment
lands on the ground directly below the point
of explosion 4.4 s after the explosion.
The acceleration of gravity is 9.81 m/s^2 .

A) Find the magnitude of the velocity of the
3.7 kg fragment immediatedly after the explo-
sion. Answer in units of m/s.


B) Find the distance between the point of firing
and the point at which the 3.7 kg fragment
strikes the ground. Answer in units of km.

C) How much energy was released in the explo-
sion? Answer in units of kJ.

Any help appreciated.
 
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Interesting problem but you need to show some effort.
 
I tried to find the velocity:

MVix = MVfx

(6)(cos(20))(125) = (3.7)(0) + (3.7)(Vf2x)
So get Vf2 is 181.40153 m/s.

But this is not the answer. I guess this is only the x component of it. How to get the y and put it together?:confused:
 
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