What Velocity Clears a Shelf in Projectile Motion?

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The discussion centers on calculating the initial horizontal velocity required for a rock to clear a shelf while falling from a cliff with a vertical drop of 6 meters and a horizontal distance of 10 meters. The problem involves understanding projectile motion, specifically the equations governing horizontal and vertical motion under gravity. The acceleration due to gravity is given as 9.8 m/s², and air friction is considered negligible. A solution was eventually found, with a request for students to show their work and equations for clarity. The discussion highlights the importance of applying the correct physics principles to solve trajectory problems.
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Homework Statement



You are standing at the top of the cliff that has a stairstep configuration. There is a vertical drop of 6m at your feet, then a horizontal shelf of 10 m, then another drop of 4m to the bottom of the canyon, which has a horizontal floor. You kick a .93 kg rock, giving it an initial horizontal velocity that barely clears the shelf below. The acceleration of gravity is 9.8 m/s^2. Consider air friction to be negligible. What initial horizontal velocity v will be required to barely clear the edge of the self below you.

Edit: Solution found.
 
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We request students show some work and write the appropriate equations.

The problem reqires an object to clear a point 6 m below and 10 m horizontally displaced, and one has to determine the horizontal velocity to achieve the trajectory to accomplish this.

What is the initial vertical velocity? What are the equations of motion in the horizontal and vertical?

See - http://hyperphysics.phy-astr.gsu.edu/hbase/traj.html#tra11 (horizontal launches)
 
I saw this exact question somewhere else, I believe on this forum. I just can't find it.
 
Astronuc said:
We request students show some work and write the appropriate equations.

The problem reqires an object to clear a point 6 m below and 10 m horizontally displaced, and one has to determine the horizontal velocity to achieve the trajectory to accomplish this.

What is the initial vertical velocity? What are the equations of motion in the horizontal and vertical?

See - http://hyperphysics.phy-astr.gsu.edu/hbase/traj.html#tra11 (horizontal launches)

I actually determined a solution for this problem (see edit) but thank you! I did have equations shown and attempted work but incidentally, I erased it all when I found a solution. It took me a while to find it but I'm slowly beginning to understand.
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
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