motion Flashcards
What does the gradient on a distance-time graph represent?
accerlaration
Vector
A physical quantity that has a direction and a magnitude
Velocity
Speed in a given direction
Displacement
Distance in a certain direction.
Scalars
A physical quantity that has a magnitude only and not a direction.
Examples of Scalars
Speed Distance Time Mass Energy Power
Examples of Vectors
Force Momentum Weight Gravitational Field Strength velocity
What does the gradient of the line on a velocity-time graph represent?
Acceleration
What does the area underneath a velocity/time graph represent?
Distance travelled.
Which of the following quantities are vectors?
mass
acceleration
force
speed
velocity
time
acceleration
force
velocity
What type of force acts forward on a rocket?
Thrust
Thrust is created when an object throws something out in one direction- such as gases.
A horizontal line on a velocity-time graph shows?
constant velocity, no acceleration
If a book is a rest on a table, what two forces are acting on it
downward gravitational pull (or weight)
upward reaction force from table
What can be done to reduce friction when an object is sliding on a surface?
- use oil or grease on the surfaces
- make the surfaces smoother
- blow air between the surfaces
explain how something reaches constant speed
When an object falls its weight causes it to accelerate towards the ground.
Resistive forces act on it in the opposite direction to its motion.
As the object speed increase the resistive force increases until these balance the downwards force of the objects weight
So there is no resultant force so it travels at a constant
