The Motion of the Center of Mass

AI Thread Summary
The discussion revolves around a projectile launched at an angle that explodes into two equal mass pieces at its peak. The first piece lands a horizontal distance D from the explosion point, and the problem requires determining the height and landing position of the second piece in terms of initial speed v0, angle theta, distance D, and time t. Conservation of momentum equations are set up for both x and y directions, but the original poster struggles to progress further. The conversation emphasizes understanding the relationship between velocity, distance, and time to solve for the unknowns. The thread highlights the complexities of projectile motion and the effects of an explosion on trajectory.
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Homework Statement



A projectile is launched with speed v0 at an angle theta with respect to the horizontal. At the peak of its motion, it explodes into two pieces of equal mass, which continue to move in the original plane of motion. One piece strikes the ground a horizontal distance D further from the launch point than the point directly below the explosion at time (t < v0 sin(theta) / g) after the explosion. How high does the other piece go? Where does the other piece land? Answer in terms of v0, theta, D, and t.

Homework Equations



Conservation of momentum
<br /> v = v_0 + a t<br />
x = x_0 + v_0 t + (1/2) a t^2
<br /> v^2 = v_0^2 + 2 a \Delta x<br />
Others?

The Attempt at a Solution



I started out by drawing a picture of the particles. I assume since the first particle hits the ground at less than half of the time of flight, it must have been directed downward. I set up conservation of momentum formulae for both the x and y directions:
2 v_0 cos\theta = v_1 cos\theta_1 + v_2 cos\theta_2
0 = v_1 sin\theta_1 + v_2 sin\theta_2
Also:
v_1 cos\theta_1 = \frac{D}{t}
I'm not sure where to go from here. All attempts seem to lead to dead ends. Any help is appreciated. Thanks!
 
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What do you know about the velocity in the x direction and in the y direction? If you have velocity and distance covered by the object, what else do you know about that object?

You know how fast the object is going in the x direction and how far it goes, so you can solve for time correct? Now, why was the ball only allowed to go as far as it did?
 
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