P1 Flashcards
What is used to measure very small distances?
micrometer screw gauge
Speed formula
total distance / total time
Define acceleration
change of velocity / total time
Acceleration is the…
gradient of a speed-time graph
Acceleration of a free fall g for a body near to the Earth is _________.
constant
What do you calculate to find the distance travelled for motion with constant acceleration.
the area under a speed–time graph
Define speed
a measure of how fast an object is moving
Earth is the source of a ___________________.
gravitational field
Define weight
W=mg
g=10N/kg
Define mass
m=W/g
The mass of a body is the _____________ in it, whereas the weight of a body is the _____________________ acting on it.
amount of matter, measurement of gravitational force
Define velocity
speed in a specific direction
same formula as speed but uses + and - signs to identify whether it is accelerating or decelerating
When something speeds up/slows down, it is:
accelerating/decelerating
3 fundamental effects of force
change in shape, size, motion(velocity)
Newton’s 2nd law of motion:
Resultant Force applied =
Mass of object X acceleration of object
F(N) = m(kg) x a(ms^-2)
Force applied is _________________ to the extension of the spring.
directly proportional
Hooke’s Law
F = kx
What does ‘k’ represent in the Hooke’s law formula?
spring content
Elastic limit
spring no longer goes back to its original length - beyond this limit, the object will behave like plastic.
What is this formula used for?
p=m/v
density
Air resistance is a form of __________.
friction
Define friction
the force between two
surfaces which impedes motion and results in
heating.
The turning effect of a force depends on applying a force…
- at 90 degrees to the hige/pivot
- as far from the hinge as possible
Define moment
the turning effects of a force
Moment formula
Force perpendicular to the hinge x perpendicular distance from pivot
moment(Nm) = F(N) x d(m)
What is the gravity of Earth?
10N/kg
Centre of mass
the point through which the weight appears to act.
How to find the centre of mass of regular-shaped objects:
- draw 2 lines of symmetry
- where the lines cross = centre of mass
Pressure formula
P(N/m^2) = F(N) / A(m^2)
Unit for pressure
(Pa)Pascal
