Topic 15 - Forces and matter Flashcards
Stretching,bending or compressing requires
more than one force
Elastic distortion is
When an object can go back to its original shape once the force is removed
Inelastic distortion is
when an object doesnt return to its orginal shape after the force is removed
Force exerted on a spring(N) =
Spring constant(N/m) x extension(m)
Energy transferred in stretching(J) =
0.5 x spring constant(N/m) x extension^2(m)
The extension or compression of a spring is directly proportional to
the load or force applied
The linear proportionality of extension and force on a spring is
Limites, and becomes non-linear after the elastic limit
Investigatign the proportionality of extension and force on a spring
Attach spring to a clamp, and set up a ruler next to it. Measure the startign length.
Add masses to the bottom of the spring, and measure the extension with each mass added
Plot the graph for force and extesnion to see the propertiobnality, and work out the spring constant of the spring
Atmospheric pressure decreases with
height
Why does atmospheric pressure decrease with height
There are fewer molecules above the height, so weight above it is less
Fluid pressure is dependant on
The properties of a fluid and atmospheric pressure surrounding it
Pressure is
the force per unit area
Pressure(Pa) =
Force(N) / Area(m^2)
Pressure in liquids increases with
Depth and density
Why does liquid pressure increase with density
There are more particles colliding, which increases the force
Why does liquid pressure increase with depth
There is more weight on top of the point
Pressure due to a column of liquid(Pa) =
Depth(m) x Density of liquid(kg/m^3) x Gravitational field strength(N/kg)
Objects in a fluid experience
upthrust
why do objects in a fluid experience upthrust
There is a force being exerted from every direction.
The bottom is deeper than the top, so it experiences a higher force than the top. This causes an upwards force
The upthrust of an object in fluid is equal to
the weight of fluid displaced
If upthrust is equal to the objects weight,
the forces balance out and the object floats
If an objects weight is higher than the upthrust,
the object sinks
