2-D kinematics challenge problem help please

[sc8]

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.)

 

[berkeman]

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?