P5: Forces and Motion [incomplete] Flashcards
Scalar [definition]:
A quantity that has magnitude but no direction
Vector [definition]:
A variable quantity that has both magnitude and direction
Force [definition]:
An influence tha occurs when two objects interact
Resultant force [definition]:
The sum of or more forces acting on the same object
Acceleration (definition)
[2]:
- The rate of change of velocity
- Measured in m/s^2
Acceleration [equation]:
Acceleration = Change in velocity(m/s)
(m/s^2) —————————————
time(s)
Circular motion (definition) [2]:
- Produced when an object rotates with a constant speed but changing velocity
- The instantaneous velocity is perpendicular to the centripetal force
Velocity time graphs [2]:
- The gradient of the line shows acceleration
- The area under of the line of best fit gives you displacement/distance
Uniform moton =
Constant acceleration
Gravitational pull on Earth:
- 8 for every 1kg of mass
9. 8N/Kg
Mass (definition)
[2]:
- A measure of how much matter an object contains
- Measured in kilograms
The mass of an object…
stays the same wherever it is
Weight can change if…
the object goes somewhere gravity is stronger or weaker
The moon is smaller than the Earth so…
it has less mass than the Earth
Weight (definition) [2]:
- The vertical downwards force acting on an object due to gravity
- Measured in Newtons (N)
Drag:
Air/ water resistant
Newton’s first law [2]:
If the resultant force acting on an object is zero it will:
- If moving, keeps moving at a steady speed in a straight line
- If stationary would remain statonary
Resultant force [equation]:
Mass(kg) x Acceleration(m/s^2)
Newton’s second law [2]:
- The acceleration of an object increases if the resultant force on it increases
- Acceleration decreases if the mass of the object increases
Inertia [definition]:
The tendency of an object/body to stay at rest or in uniform motion
Upthrust is equal to…
the weight of the object that has been forced away
A partially submerged object would experience…[2]:
- Greater pressure on the bottom surface than the top surface
- This creates a resultant force upwards (upthrust)
Floating [2]:
- When the object’s weight is equal to the upthrust
- The forces then balance and the object will float on the liquid
Sinking [2]:
- When an object’s weight is greater than the upthrust
- Then the object will sink
Pressure difference [equation]:
density of fluid x gravitational field x change in depth
strength
Momentum [equation]:
Momentum = Mass x Velocity
(kgm/s) (kg) (m/s)
Conservation of momentum:
When two objects collide or interact, the forces acting on each other will stay the same
Momentum [equation]:
Momentum = Mass x Velocity
(kgm/s) (kg) (m/s)
Conservation of momentum:
When two objects collide or interact, the forces acting on each other will stay the same
What happens to the momentum of an object when it is stationary?
Momentum is 0; there is no momentum
Newton’s first law:
-
Newton’s third law:
-
