Slingshot Physics: Calculating Projectile Speed from a Building's Height

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To calculate the speed of a pebble striking the ground from a 31.0m tall building when fired from a slingshot at 14.0m/s, the discussion focuses on three scenarios: horizontally, vertically up, and vertically down. For horizontal firing, the initial vertical velocity is zero, while for vertical up, it is 14.0m/s, and for vertical down, it is also 14.0m/s. The equations of motion are applied to determine the final speed upon impact, taking into account gravitational acceleration. Participants emphasize using the correct initial velocities for each scenario and applying the equations of motion effectively. Understanding these principles is crucial for solving the problem accurately.
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This one has me stuck, any help would be greately appreciated, cheers, mac


A slingshot fires a pebble from the top of a building at a speed of 14.0m/s. The building is 31.0m tall. Ignoring air resistance, find the speed with which the pebble strikes the ground when the pebble is fired (a) horizontally, (b) vertically straight up, (c) vertically straight down.
 
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You'll need the y-component of your initial velocities. What are they for each of those 3 scenerios?

Start with that and see how far you get.
 
haha do ur physics homework urself, or dr bao will get u :@:@ haha only kiddin mate, u worked out any of the answers yet,
thanks dilo
 
Start with the good old-fashioned equations of motion in the x- and y-directions:

x=x_0+v_xt

y=y_0+v_yt-\frac{1}{2}gt^2

v_y=v_{y0}-gt
 
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