IPC EXAM 2

Ch. 13.1 13.2 13.3 14.1 14.2 14.4 15.1 15.2

how does pressure exerted by the atmosphere change as altitude increases?

air pressure decreases as altitude increases

How is pressure distributed in a fluid?

It is exerted equally in all directions of the fluid

pressure

result of a force distributed over an area

a fluid

substance that assumes the shape of its container

according to pascal’s principal…

a change in pressure at any point is transmitted equally and unchanged in all directions throughout the fluid

hydraulic system

device that uses pressurized fluid acting on pistons to change a force

How can a hydraulic lift system increase force?

a constant fluid pressure is exerted on the larger area of the output piston

How are fluid speed and fluid pressure related?

As the speed of a fluid increases, the pressure within the fluid decreases

a lift

when the air-travel over the wing is moving faster than the air-travel under the wing, creating an upward force

buoyancy

fluid’s ability to exert an upward force on an object placed in it

What affect does buoyancy have on an objects weight?

objects inside a fluid have an apparent lose in weight

buoyant force

when a submerged object is acted upon by an upward force, making the submerged object easier to lift

Archimedes principal

the buoyant force on an object is equal to the weight of the fluid displaced by the object

How can you tell if an object will float or sink in a fluid?

an object less dense than it’s fluid will float, an object more dense than the fluid its in will sink

units for pressure

pascal (Pa)

units for density

g/cm³

the object will be suspended

when it has the same density of the fluid it is in

density formula

density = mass / volume

work

the product of force and distance

if there is no motion

there is no work

for a force to do work on an object

some of the force must act in the same direction as the object moves

any part of a force that does not act in the direction of motion does no work on a object

true

work formula

work = force x distance

units for work

joule (J)

power

the rate of doing work

doing work at a faster rate requires

more power

to increase power

increase amount of work done in a given time

power formula

Power = work/time

One horsepower

746 watts

units for power

watt (W) = 1 Joule per second

machine

devise that changes work

how do machines make work easier?

they change the size, direction, or distance the force acts over

input force

force exerted on a machine

output force

force exerted by a machine

the distance the input force acts through

input distance

work input

work done by input forcing acting on input distance

output distance

distance output force is exerted through

how many types of simple amchines are there?

6

fixed point the the bar rotates around

fulcrum

To calculate ideal mechanical advantage of any lever…

divide input arm by output arm

example of a first class lever

opening paint can using a screw driver

example of a second class lever

wheelbarrow

example of a third class lever

someone sweeping, input force is hand on middle of broom, fulcrum is the hand on the top of broom, and output force is the broom sweeping

to calculate ideal mechanical advantage of a wheel and axle

divide radius where input force is exerted by radius where output force is exerted

Does a thick wedge or a thin wedge have a greater mechanical advantage? (they are the same length)

thin wedge

screws with threads closer together have a ____ mechanical advantage

greater

it takes energy to do…

work

Elastic potential energy

energy of an object that is stretched or compressed

work is a transfer of…

energy

energy of motion

kinetic energy

Potential Energy

energy stored as a result of position or shape

gravitational potential energy

PE that depends on an object’s height

mechanical energy

sum of an objects PE and KE

Chemical energy

energy stored in chemical bonds

electrical energy

energy associated with electric charges

an object’s gravitational PE depends on its…

mass, height, and acceleration due to gravity

electromagnetic energy

form of energy that travels through space in the form of waves

nuclear energy

energy stored in atomic nuclei

energy conservation

changing energy from one form to another

einsteins equation states that energy and mass…

are equivalent and can be converted into each other

Einstein’s equation

Energy = mass x constant for speed of light

constant for speed of light

3 × 10⁸ m/s