Mechanics Flashcards
Define distance
The physical distance between two points
Define displacement
The distance travelled in a certain direction
Define speed
The rate of change of distance with time
Define velocity
The rate of change of displacement with time and must include direction
State the formula, with the correct SI units, for speed and velocity
v = s/t
State the formula for average speed
Average speed = Total distance/Total time
Define acceleration
The increase in velocity of a body
State the formula, with the correct SI units, used to calculate acceleration
a = v/t
State what is calculated when the area under a velocity/time graph is calculated
Distance
Distinguish between mass and weight
Mass refers to the amount of matter in an object, while weight refers to the amount of gravitional pull that the earth exerts on an object
State the formula for weight, using the correct SI units
w = m x g
Define inertia
The property of matter to resist change unless acted upon by an external force
State why it is important to wear seatbelts when travelling, referring to inertia
Seatbelts act against inertia, protecting a person from colliding with someting incase of a sudden change in speed, for example in the case of a car accident
Define a force
A push or a pull exerted on an object
Name four effects that a force can have on an object
- Change in size or shape
- An object can break
- The motion of an object can be changed
- The position of an object can be changed