7TH GRADE PRACTICE
Physics Problems: Archimedes' strength and swimming, Grade 7
Pushing, navigation conditions, ships and aeronautics.
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Problem statements
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Problem #43
Archimedes' powerEvaluate the statement: The resultant force of pressure of a liquid or gas on a submerged body, directed upward.
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The lower body is usually deeper and experiences more pressure, causing a net upward force.
Answer
Problem #44
Archimedes' powerEvaluate the statement: the concept “Archimedes’ Law” means: The buoyant force is found as the difference in the dynamometer readings in the air and when the body is immersed.
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The force depends on the density of the medium, the acceleration of gravity and the displaced volume, but not on the depth in a homogeneous medium.
Answer
Problem #45
Archimedes' powerThe block is completely immersed in water and displaces 0.002 m³. Find the Archimedean force for a water density of 1000 kg/m³ and g = 9.8 m/s².
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Answer
Problem #46
Floating bodies, ships and balloonsEvaluate the statement: A floating body is in equilibrium when the buoyant force is equal in magnitude to the force of gravity.
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If the average density of a body is less than the density of the liquid, it floats up and sinks only partially.
Answer
Problem #47
Floating bodies, ships and balloonsEvaluate the statement: The concept of "Sink and rise" means: Hollow vessels and balloons use a large displacement volume to obtain the required buoyant force.
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By changing the average ballast density or the volume of the gas shell, underwater vehicles and balloons are controlled.
Answer
Problem #48
Floating bodiesThe average density of a dry wooden block is 800 kg/m³, the density of water is 1000 kg/m³. What happens to the block after a quiet dive?
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Equilibrium will be established upon partial immersion.
Answer
The theory behind these problems
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Formulas by topic
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