Describing movement Flashcards
What is a distance-time graph?
A distance-time graph plots distance travelled on the vertical axis and time on the horizontal axis to describe the movement of an object.
Why are graphs more useful than words for describing movement?
Graphs are useful because:
• They make it easier to see trends and patterns. • You can read any value of distance or time from the graph. • Other values, such as speed, can be calculated from the graph. • They provide a clear overview of the entire journey.
How can speed be calculated using a distance-time graph?
can be calculated from the slope of the graph:
Speed= Distance/ Time
Describe the movement shown by a straight, upward-sloping line on a distance-time graph.
A straight, upward-sloping line represents constant speed. The object is travelling the same distance in each second.
What does a horizontal line on a distance-time graph represent?
A horizontal line represents an object that is stationary (at rest), meaning it is not moving, and the speed is zero.
In a distance-time graph, what does the starting point A represent?
The starting point A represents the initial position of the object where the distance travelled is zero.
Explain the movement from point A to point B as shown in the distance-time graph.
From A to B, the object travels at a constant speed, as indicated by the straight, upward-sloping line.
What does the term “stationary” mean in a distance-time graph?
Stationary means the object is not moving, and the speed is zero. The distance does not change, but time continues to pass.
What does a steeper straight, upward-sloping line represent on a distance-time graph?
A steeper straight, upward-sloping line represents an object moving at a faster speed. It covers a greater distance in each second.
What does a straight, downward-sloping line indicate in a distance-time graph?
A straight, downward-sloping line indicates that the object is returning to the starting position, and the distance from the start is decreasing.
In a distance-time graph, what does it mean if there is a horizontal line?
A horizontal line means that the object is stationary, with no change in distance over time.
What is the equation to calculate speed using a distance-time graph?
A train leaves station P at time 0 and travels to station R, which is 2000 m away, in 200 s. What is the speed of the train from P to R?
After stopping at station R for 140 s, the train travels back to station P in 100 s. What is the speed of the train on the way back from station R to P?
How can distance-time graphs be used for calculations?
What are the key events in the train journey example shown in the distance-time graph?
- The train leaves station P at time 0.
- It takes 200 s to travel from P to R.
- The train stops at station R for 140 s.
- The train returns to station P in 100 s.
How far did the boat travel when crossing the lake once?
The boat traveled 80 meters when crossing the lake once, as shown by the peak of the graph on the y-axis.
How do you calculate the speed of the boat crossing the lake the first time?
The speed is calculated by dividing the distance by the time. In this case, speed = 80 meters / 40 seconds = 2 meters per second.
How much time did the boat spend stopped before crossing the lake again?
The boat was stopped for 60 seconds, as indicated by the flat part of the graph from 40 seconds to 100 seconds.
How do you calculate the speed of the boat crossing the lake the second time?
How much time did the boat take for the complete journey?
The total time for the complete journey was 132 seconds (crossing the lake twice and stopping in between).
