Projectile Motion Cat Ledge Problem Solution

[kj99]

Homework Statement

A cat leaps over a 1.5m wall with a speed of 15m/s and at an angle of 35 degrees. The cat lands on the edge of a ledge that is 1.5m tall, how far is the ledge from the wall?

Homework Equations

The Attempt at a Solution

I used the range equation to find the entire horizontal distance it could have traveled if there was no ledge (21.14m). Then subtracted that by the distance between the cat and the wall (Pythagorean theorem) and also subtracted that by the distance between the ledge and where it would have landed if there was no ledge. I got a distance of 16.86m and it's wrong lol.

 

[Dr. Courtney]

Need a good diagram.

 

[haruspex]

... the distance between the cat and the wall

I don't understand how you calculated that.
Also, it is unclear whether the cat reaches its highest point before or after clearing the wall. Is there more info?
Whatever, it's one hell of a cat.

 

[kj99]

I don't understand how you calculated that.
Also, it is unclear whether the cat reaches its highest point before or after clearing the wall. Is there more info?
Whatever, it's one hell of a cat.

It jumps at 35 degrees and the wall is 1.5m so tan35=1.5/x.
It reaches its max height after the wall and lands on the 1.5m tall ledge.

 

[haruspex]

It jumps at 35 degrees and the wall is 1.5m so tan35=1.5/x.
It reaches its max height after the wall and lands on the 1.5m tall ledge.

I would think the given angle is the take off angle. Indeed, you assumed that to get the 21m distance. That will be higher than the angle from take off point to top of wall.

 

[CWatters]

I don't think it can be answered without a diagram to provide more information.

 

[J Hann]

Have you tried using the initial x and y components of the initial velocity and then
calculating the time required to reach a final height of 1.5 m?