Science - Forces & Movement Flashcards
What are the two ways forces can be categorized?
Contact or Non-Contact
Push or Pull
What is a Contact and a Non-Contact force?
Non-Contact forces can act from a distance like Gravity or Magnetism.
Contact forces are touching/in-contact with the body having the force exerted upon it like Friction and Normal force.
What does Push or Pull describe?
Push or Pull describes whether the body having a forced exerted on it goes towards or away from the body exerting the force.
Describe Gravity
It’s a Non-Contact Pulling force.
Describe Normal Force
It’s a contact force
A force can cause an object to
- Change Direction
- Change Shape
- Change Speed ( Speed up & Slow down)
What is a Gravitational force?
This is the attractive force exerted between bodies because of their
masses.
How does Gravitational force increase/decrease?
This force increases if either or both of the masses is increased and
decreases if they are moved further apart.
What is Normal force?
This is the repulsive force that stops two touching bodies moving into each other.
What causes Normal force?
It is caused by repulsive molecular forces.
What is Friction Force?
This is the force that opposes motion.
The kinetic energy of the moving object is converted to heat energy by the force of friction.
What other forces are a type of friction.
Water and air resistance are also a type of friction, and will oppose the motion of the body traveling through it.
What is Upthrust?
This is the force experienced by objects when they are placed into a fluid (liquid or gas).
Describe Upthrust
An object will float on a fluid if the upthrust force equals its weight. If upthrust is bigger, then it’ll rise, if it’s lower it’ll fall.
What is Magnetic force?
It is a force between magnets and also is the force that allows electric motors to work.
What is Electrostatic Force?
Attractive and repulsive forces due to bodies being charged.
What are all physical quantities described by?
All physical quantities (e.g. speed and force) are described by a magnitude (a value) and a unit.
What describes magnitude and units?
- Vectors - Have magnitude and also direction specified. Examples: displacement, velocity, acceleration, force.
- Scalars – do not have a direction only magnitude. Examples: distance, speed, mass, work, energy.
How do you represent Vectors?
An arrowed straight line is used.
The arrow indicates the direction and the length of the line is proportional to the magnitude.
What are the original and final overall vectors called?
- The original vectors are called COMPONENT vectors.
- The final overall vector is called the RESULTANT vector.
What is a resultant force?
A number of forces acting on a body may be replaced by a single force which has the same effect on the body as the original forces all acting together.
This overall force is called resultant force.
Name The 8 Energy Stores
- Chemical
- Elastic
- Gravitational Potential
- Nuclear
- Kinetic
- Magnetic
- Thermal
- Electrostatic
Name The 4 Energy Transfers
- Heating
- Electrical
- Radiation (light, EM waves and sound).
- Mechanical
What is the equation of efficiency?
Efficiency = Total Energy Transferred By Device / Total Energy Supplied To Device
What is Distance?
The total movement of an object without any regard to direction.
What is Speed?
Speed is measured as the ratio of distance to the time in which the distance was covered.
What is Velocity?
Speed in a given direction.
What is Average Speed?
Total distance divided by total time.
What is Instantaneous Speed?
The speed at one given moment.
What is Acceleration?
The rate of change of speed.
What Do These Mean In Graph Lines:
- Diagonally Up
- Horizontal
- Diagonally Down
- Gradient
- Area under graph
- Constant Acceleration
- Constant Speed
- Constant Deceleration
- This is the acceleration/deceleration of the object
- This is the distance travelled by object
What is the equation for acceleration
Final Velocity - Start Velocity Divided by Time
