can someone please help me with this CX? Suppose you launch two identical projec

Question

      can someone please help me with this CX?
Suppose you launch two identical projectiles from an elevated position (well above ground level) at the same initial speed, but at different angles. Which one, if either, will have a greater speed at impact on the ground?

Requirements

Launch angles must be between either 20-70°; the two angles you choose must differ by at least 15°

Only use equations from the Two-dimensional motion, constant acceleration section of the PHYS 1200 Equation Sheet, and any trig you need

To answer this question, create a specific experiment (choose the elevated position, the projectiles, their launch speed and launch angles), then solve so you can answer the question, using only equations from the Two-dimensional motion, constant acceleration section of the PHYS 1200 Equation Sheet.

Write up your solution as described in the information in this folder, and either bring your work to class or submit a single document in PDF, DOC, or DOCX format using the CX1 link above.

Explanation / Answer

let initial speed be v.

launch angle be theta.

then initial horizontal velocity=v*cos(theta)

let height above ground be h .

initial vertical velocity=v*sin(theta)

if vertical speed when the projectile reach ground level is v1,

then using the formula:

final speed^2-initial speed^2=2*acceleration*distance

==>v1^2-(v*sin(theta))^2=2*g*h

==>v1=sqrt(v^2*sin^2(theta)+2*g*h)

so total speed at the ground level on impact

=sqrt(vertical speed^2+horizontal speed^2)

=sqrt(v^2*cos^2(theta)+v1^2)

=sqrt(v^2*cos^2(theta)+v^2*sin^2(theta)+2*g*h)

=sqrt(v^2+2*g*h)

so the speed on impact does not depend upon launch angle.

hence both will have same speed on ground impact.

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