science final Flashcards
(55 cards)
aquifer
an area of
porous rock with a water system
flowing through it
erosion
the movement of sediments
from one place to another
glacier
a large moving mass of
compressed ice and snow
crevasse
a deep fissure or crack in ice
striations
scratches made in rocks
by rock fragments carried by
glaciers
cirques
a bowl shaped basins eroded by valley glaciers
aretes
a mountain ridge carved by
two or more glaciers from several
directions
moraine
a landform made of glacial till
esker
a winding ridge made of
sand and gravel formed by streams
that flow beneath a glacier
tidal range
the difference in the
water level between high tide and
low tide; varies with the shape of
the shoreline
spring tide
the largest tidal
movements; occur when Earth,
Moon, and Sun are lined up
detritus
organic matter produced
by decomposition, such as decaying
bodies of plants and animals
potable
safe to drink
phytoplankton
the plant organisms in
plankton
Class 1, 2, 3 levers (Effort, Load, Force and examples of each)
Class 1: the fulcrum is in between the effort and the load, e.g = teeter totter, broom, crowbar, scissors, pliers
Class 2: the load is between the fulcrum and the effort, e.g. = wheelbarrow, bottle opener, oar
Class 3: the effort is between the load and the fulcrum, e.g = hockey stick, lacrosse stick, fishing rod, baseball bat, tweezers
Winch, gears, chain gears - what do they do, how do they work etc
Winch - it’s used to pull up heavy things, like boats, onto a platform. It works like a lever and you turn the handle, that turns a wheel to pull up the boat
Gears - gears have many uses but they spin to move other things using the teeth around their rims. They have teeth on their rims and the teeth fit into other gears, or other things and when you spin the driver gear the rest of the train or thing moves/spins.
Sprocket - typically used in bike chains, the large one turns to move the small one many times to move the wheels or other things faster. Works by putting a small and large gear in a chain link, moving the big one moves the small one many times making the system move very fast.
Pulleys - fixed and movable (what’s the difference and purpose of each)
A grooved wheel with a rope or chain running along the groove
Fixed pulleys are pulleys that are attached to the roof or something that can’t move, and the pulley itself doesn’t move
Moveable pulleys are put on the rope in a way that has them move up and down with the load to move the load.
Know examples of when work is being done
When you exert force on something and it moves a distance away from where it started. When you lift a box off the ground straight up, when you push a sled forward, not when you hold something up.
What ever way your exerting force on something, if it travels in that direction that is work, but if you exert force on an object in one direction and head the other, no work is done - carrying a backpack down the hall, or holding a pole up
Mechanical Advantage (formula M=LF/EF)
The comparison of force produced by a machine to the force applied by the machine
Mechanical advantage = load force/effort force
Hydraulic system vs pneumatic system
What would happen if a hydraulic system had a leak and lost some of its fluid?
It wouldn’t work, because the system relies on the fluid being contained so that the pressure exerted on the fluid is transmitted, but to lose some of the liquid it wouldn’t have the right amount to push the proper force and would no longer be contained.
What happens when gas is compressed in a closed container?
It increases the pressure on the gas, the volume decreases, and the pneumatic system works because the gas is compressed and put under high pressure.
Steam vs internal combustion engines (diesel, gasoline) - what’s the difference
Steam engines burn their fuel outside of the engine while internal combustion engines burn their fuel inside the engine. Steam engines are also slower because it takes more time for the steam to reach the piston.
Steam turbine vs steam engine (differences and how they work)
The steam turbine uses wheels with blades and spins to work, while steam engines use pistons to work. The steam turbine burns fuel, creates the steam, then has the steam travel through the blades to spin the wheels, the old steam then exits the engine at the other side of the wheels. The steam engine uses the steam to push a piston forward, then travels to the other side to push the piston back, then exits the engine.
Airbags - why and how do we use them?
We use airbags to protect and reduce the chance of death when we get into a car crash, the airbags are used to spread out the pressure force of the impact of a car on the front of the car.
