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16 Cards in this Set
- Front
- Back
Define 'density'
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A value that tells you how many kg there are per 1m cubed
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Why do we need to know density?
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It helps identify whether one material will sink in another
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Equation for density?
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Density = mass/volume
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Unit for density?
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kg/m3
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What effect does heat have on density?
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If we heat a substance, the molecules spread out. This means the volume increases. Heating an object decreases the density.
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Describe an experiment to find the density of an irregular object.
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Lower into displacement jug and measure water displaced. this is the volume. Measure three times and take average for more accurate results
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What is pressure?
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Force per unit area.
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What is the equation for pressure?
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Pressure = Force/Area
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Units for pressure?
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N/m2 or N/m3 (Pa)
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How do you convert cm2 into m2?
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divide by 10,000
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Smaller area = ..... pressure
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Higher
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The pressure at a point inside a liquid or gas is .....
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The same in all directions
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As we get deeper in water and air the pressure .....
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Increases
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Equation for pressure difference
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Pd = pressure x height x gravity
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Explain the theory behind hydraulics
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If we apply pressure to a fluid, it transfers this pressure elsewhere.
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Describe how hydraulics work
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Put a small force on a small area, and a larger force on a larger area is created because the pressure remains constant.
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