P5 - Forces 1 Forcesand Their Interactions Flashcards
What is a scalar quantity ?
- A quantity that only has a magnitude
What is a vector quantity ?
A quantity that has both a magnitude and direction.
How can a vector quantity be drawn and what does it show ?
- As an arrow
- The length of the arrow represents the magnitude
- The arrow points in the associated direction
What is a force ?
A push or pull acting on an object due to an interaction with another object
What are the two categories that all forces can be split into ?
- Contact forces (object touching)
- Non-contant forces (objects separated)
Give three examples of contact forces
- Friction
- Air resistance
- Tension
Give three examples of non-contact forces
- Gravitational forces
- Electrostatic forces
- Magnetic forces
Is force a vector or a scalar quantity ?
- vector
- it has both a magnitude and an associated direction
Give three examples of vector quantities
- Velocity
- Displacement
- Force
Give examples of scalar quantities
- temperature
- time
- mass
- speed
- distance
- energy
What is weight ?
The force that acts on an object due to gravity and the object’s mass
What quantities does weight depend on ?
Weight = mass x gravitational field strength
- the objects mass
- the gravitational field strength at the given position in the field
What is the unit used for weight ?
The Newton (N)
What is the unit used for gravitational field strength ?
N/kg
What is meant by an objects centre of mass ?
The single point where an object’s weight can be considered to act through.
