Science exam 8.3-9.3

Description:	1-9 projects that we did
Category:	Physics
Created by:	jlarose on 2008-11-19

Question	Answer
___________ is a fluid's resistance to flow(how difficult it is for fluid to flow)	Viscosity
If a fluid is thick, the viscosity is:	greater, flows slower
The ____________ is the speed at which a liquid flows	flow rate
when _________ the particles in a substance move further apart	heated
when gasses are heated the viscosity of the gas _________	increases
when liquids are heated, the viscosity of the liquid _______	decreases
_____________ is the property of fluids that makes the particles hold together because they are attracted to each other	cohesion
_____________ is the effect that the particles at the surface attract each other and form a "skin"	surface tension
___________ is the attraction between particles of a fluid and another substance so that the fluid clings to it	adhesion
in a gas or a liquid, the deeper you go, the ______ the pressure is	greater
in a gas or a liquid, the deeper you go, the greater the pressure is because	there is more air or liquid above the point pushing down
because of all the air in the atmosphere, the pressure at sea level is a little more than:	100kPa
100kPa is called:	one atmosphere
the ____________ you go in a gas or a liquid, the less pressure there is	higher
for every 10m deeper in water, the pressure increases by:	1 atmosphere
________ is the tendency for objects to rise or float in a fluid	buoyancy
buoyancy occurs because:	differences in density of the object and the fluid
______________ is the force of the fluid pushing up on the object	buoyant force
hot air rises because of buoyant force on the hotter air. this process is called:	convection
ovjects float or sink based on:	whether the buoyant force is greater or less than the gravitational force
when pressure is applied at one point in a fluid in an enclosed system, that pressure is transmitted _____ thoughout the entire system.	qually
when pressure is applied at one point in a fluid in an enclosed system, that pressure is transmitted equally thoughout the entire system. called:	static pressure
________ is the sideways pressure exerted by a fluid in motion	dynamic pressure
as the speed of a fluid increases, the dynamic pressure __________	decreases
________________ are systems that use pressure in liquids to do work	Hydraulic systems
(true or false) since liquids aren't normally compressible, applying a force to a liquid transmits the force along the liquid	True
2 important parts of hydraulic systems are _____ and _____	pumps and valves
what do pumps do in the hydraulic system?	put the liquid under pressure
what do valves do in the hydraulic system?	control the passage of the liquid through a pipe
Hydraulic systems can also be used to:	multiply the force exerted by a liquid
_____________ are systems that use pressure in gases to do work	pneumatic systems
since gases can be compressed, pneumatic systems use ______	compressors
the gas is compressed and then when the pressure is released, the expansion of the gas causes:	a short burst of strong, steady force to do work
common problems in pneumatic systems are:	1. loss of pressure due to leaks in the system 2. reduction of the gas flow due to blockage of the passageway
The ________ transports blood throughout the body	circulatory system
the _____ is the pump which moves the blood through the blood vessels	heart
the blood is kept under pressure to move it to all parts of the body. each beat _____ the pressure, and then it falls again before the next beat	inreases
blood pressure is measured with a :	sphygmomanometer
blockages in the vessles cause increased pressure, which can cause them to:	burst
the ______ brings air into the body and removes corbon dioxide from the body	respiratory system
_____ changes the air pressure to make the air move	breathing
when you inhale, the increased space _____ the air pressure inside your lungs, so the higher pressure outside pushes air in	reduces
when you exhale, the _____ and ribs compress the air in your lungs and so it is pushed out of the body	diaphragm
infections and diseases such as asthma _____ the air passages, resulting in difficulty breathing	narrows
when you breathe in:	the diaphragm moves down and the chest cavity expands
when you breathe out:	the diaphragm moves up and the chest cavity contracts