2-D kinematics challenge problem help please

AI Thread Summary
The discussion centers on solving a 2-D kinematics problem involving two artillery shells fired at different angles, with the goal of determining the time elapsed between the firings. The initial velocity for both shells is 250 m/s, with angles of 49 degrees and 20 degrees. Participants suggest using kinematic equations for vertical and horizontal displacement to find the collision point of the shells. The key approach involves writing separate equations for each shot, accounting for their different angles and firing times, and setting their positions equal to solve for the time difference. This method will help in understanding the projectile motion and finding the solution to the problem.
sc8
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Homework Statement
Please help with this problem, I am unsure what equations to use.
Relevant Equations
Not sure! Definitely using the angles though. (already found v not x and v not y!)
Hi! I can't solve this. Please someone give me a hint and help? I'm unsure what equation to use. Thank you!🙏🙏🙏

An artillery crew demonstrates its skill by firing a shell at an angle of 49 deg and then lowering the gun barrel and firing a second shell at a smaller angle of 20 deg in such a way that the two shells collide in midair. The initial velocity of the shells is 250 m/s. Find the time elapsed between the two firings. Neglect air resistance.
(Sometimes, the shells actually collide below the level of the gun barrel: that is OK, because the gun is at the edge of a cliff.)
 
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sc8 said:
Homework Statement:: Please help with this problem, I am unsure what equations to use.
Relevant Equations:: Not sure! Definitely using the angles though. (already found v not x and v not y!)

Hi! I can't solve this. Please someone give me a hint and help? I'm unsure what equation to use. Thank you!🙏🙏🙏

An artillery crew demonstrates its skill by firing a shell at an angle of 49 deg and then lowering the gun barrel and firing a second shell at a smaller angle of 20 deg in such a way that the two shells collide in midair. The initial velocity of the shells is 250 m/s. Find the time elapsed between the two firings. Neglect air resistance.
(Sometimes, the shells actually collide below the level of the gun barrel: that is OK, because the gun is at the edge of a cliff.)
Please show us the kinematic equations for the vertical and horizongal displacement of a projectile. Then write the two equations for the two different shots with different starting angles and different starting times, and set the two positions equal (the collision point) to solve for the missing time. Can you show us that work?
 
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