9.1 Describing motion Flashcards
Slide 1.1
What is distance?
Distance is a measure of how far apart objects are from each other.
What is speed?
Speed is a measure of how fast something moves.
How do you convert between km/h and m/s according to the SI units?
To convert between km/h and m/s, you multiply the speed in km/h by 3.6 to get the speed in m/s.
What is average speed?
Average speed is a measure of how fast something moves overall.
What is instantaneous speed?
Instantaneous speed is your speed at a particular instant.
What formula is used to calculate average speed?
The formula for average speed is:
average speed = distance travelled / time taken
What formula can be used to calculate distance, speed, or time?
The formulas are:
distance = speed x time
time = distance / speed
speed = distance / time
What does a distance-time graph show?
A distance-time graph shows how far an object travels as time progresses.
What tool is suggested to help with speed calculations?
using the “speed triangle” to help with speed calculations.
What do the different slopes in a distance-time graph indicate?
- A flat line indicates that motion has stopped
- A steep slope indicates the object is covering a greater distance
- A gentle slope means the object is moving slowly
- A steep slope means the object is moving fast
What does the gentle slope in the distance-time graph indicate?
The gentle slope in the distance-time graph indicates that the object is moving slowly.
What is the relationship between the slope and the object’s average speed?
The gradient or slope of the distance-time graph is equivalent to the object’s average speed over the time interval.
What does the steep slope in the distance-time graph indicate?
The steep slope in the distance-time graph indicates that the object is moving fast.
What does the flat line in the distance-time graph indicate?
The flat line in the distance-time graph indicates that the object is not moving.
What does the area below a speed-time graph represent?
The area below a speed-time graph gives the distance that the object has travelled up to that point.
How can you calculate the gradient (average speed) of the distance-time graph?
To calculate the gradient (average speed), you can choose 2 points on the graph and use the formula:
gradient = rise / run
What does a speed-time graph show?
A speed-time graph shows an object’s speed changes over time.
What are the different ways an object’s speed may be represented on a speed-time graph?
An object’s speed may:
- Be constant, shown as a flat line
- Increase, shown as a graph rising upwards
- Decrease, shown as a graph falling downwards
What does the slope of a speed-time graph indicate?
The slope of a speed-time graph indicates whether the motion is speeding up, slowing down, or constant.
What does the slope of a speed-time graph represent?
The slope of a speed-time graph represents the acceleration of the object.
How can the area under the speed-time graph be calculated?
The area can be calculated by counting the squares or by using area formulas.
state about the relationship between the area under a speed-time graph and the distance travelled?
“The area under a speed-time graph gives the distance that the object has travelled up to that point.”
How does the steepness of the slope relate to the acceleration?
The steeper the slope of the line, the greater the acceleration.
How can you determine if the object is speeding up or slowing down based on the slope?
- If the line slopes upward from left to right, the object is speeding up. The acceleration will be positive.
- If the line slopes downward from left to right, the object is slowing down. The acceleration will be negative.
