projecilte question needs help (1 Viewer)

susanpowell

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a horizontal drainpipe 6m above sea empties storm water into the sea. If the water comes out horizontally and reaches the sea 2m out from the pipe, find the initial velocity of the water taking g to be 10m/s and ignoring air resistance

could someone do this using those 3U projectile formulas? (not physics)


thnks!
 

susanpowell

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thanks drogonski but i'm a bit confused at the end, isn't the final figure the answer to the horizontal velocity? X = V(horizontal) x T and not the overall velocity? :cry:

your answer is correct btw :p
 

Drongoski

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thanks drogonski but i'm a bit confused at the end, isn't the final figure the answer to the horizontal velocity? X = V(horizontal) x T and not the overall velocity? :cry:

your answer is correct btw :p
My answer is based on the initial horizontal velocity: i.e. velocity at time t=0. x-dot refers to the horizontal velocity and x-dot(0) the initial horizontal velocity.

You can look at it this way. The velocity can be considered to be made up of 2 components: the horizontal (which since it is not subject to any force horizontally remains unchanged throughout) and the vertical component which initially (i.e. when t=0) = 0 m/sec but with the passage of time gains velocity because of the acceleration 10m/sec/sec due to gravity.
 
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susanpowell

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ah ok so correct me if i'm wrong


to answer the question u just need to find the intitial horizontal velocity because it is the same as the initial velocity?
 

Drongoski

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ah ok so correct me if i'm wrong


to answer the question u just need to find the intitial horizontal velocity because it is the same as the initial velocity?

yes. precisely.
 
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