Topic 2 - Motion And Forces Flashcards
What is a scalar quantity?
- A quantity that only has a magnitude
- A quantity that isn’t direction dependent
What is a vector quantity ?
A quantity that has both a magnitude and an associated direction.
How can a vector quantity be represented ?
Using vector arrows
How do vector arrows represent vectors?
- The length of the arrow represents the magnitude
- The arrow points in the associated direction
Give 3 examples of vector quantities
- Velocity
- Displacement
- Force
Give examples of scalar quantities
- temperature
- mass
- time
- speed
- distance
- energy
What is velocity ?
The speed of an object in a specific direction
Give an equation linking speed , distance and time
Average speed = distance / time
On a distance time graph , what value does the gradient of the line represent ?
The speed
On a displacement / time graph, what does the gradient of the line represent ?
The velocity
How do you calculate speed at a given time from a distance - time graph for an accelerating object?
- Draw a tangent to the curve at the required time
- Calculate the gradient of the tangent
State the equation for the average acceleration of an object. Give appropriate units
Acceleration = change in velocity / time taken
a = m/s^2. V = m/s. t = s
Give an equation linking final velocity with initial velocity , displacement and acceleration
V^2 = u^2 + 2as
How can the distance travelled by an object be calculated from a velocity-time graph?
It is equal to the area under the graph
On a velocity/time graph, what does the gradient of the graph represent?
The acceleration.
State a typical value for the speed of sound
330 m/s
What is a typical value for human walking speed?
1.5 m/s
What is a typical value for human running speed?
3m/s
What is a typical value for human cycling speed?
6m/s