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The pressure from water at a depth ๐ is 21560 pascals.
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Find the depth ๐ using a value of 1000 kilograms per metre cubed for the density of water.
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Okay, so in this question, weโve got some water.
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And weโre looking at the pressure exerted by that water at a certain depth, which weโve called ๐.
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In other words, if we were to place a random object at this depth below the surface of the water, depth ๐, weโve been told the pressure exerted by the water on the object at this depth.
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And we need to figure out what the depth actually is.
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To do this, we can recall the equation that gives us the pressure exerted by a liquid at a certain depth.
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The equation in question tells us that the pressure exerted by the liquid at a certain depth is equal to the density of the liquid multiplied by the gravitational field strength of the Earth multiplied by the depth in question.
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Now in this case, weโre trying to find out the value of ๐.
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So we need to rearrange the equation by dividing both sides by ๐๐.
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Doing this leaves us with ๐ divided by ๐๐ on the left-hand side and ๐ on the right-hand side, at which when we can substitute in values.
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Weโve been told that the pressure firstly is 21560 pascals.
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So we substitute that in.
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And then weโve been told that the density of water is 1000 kilograms per metre cubed.
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And the liquid weโre studying in this question is actually water.
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So we substitute that in as well.
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And finally, we need to sub in the value of the gravitational field strength on Earth.
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Now we havenโt actually been given this information in the question.
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But luckily, we can recall that the gravitational field strength of Earth is a constant at 9.8 meters per second squared.
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So we sub that value in as well.
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Now at this point, we can evaluate the left-hand side of the equation to give us a value of ๐.
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When we do this, we find the value of ๐ to be 2.2 metres.
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Hence, this is our final answer.