Question

1. choose the best answer.

what is a distance - time graph used for in science?
to show the relationship between an objects distance and time
to show the relationship between an objects force and motion
to show the relationship between an objects mass and acceleration
to show the relationship between an objects speed and velocity

1. choose the best answer.

what does the slope of a line on a distance - time graph represent?
speed at which an object is traveling
time taken to travel a specific distance
mass of the object
distance traveled over a specific time period

1. choose the best answer.

what does the horizontal line on a distance - time graph represent?
the object is not moving.
the object is moving at a constant speed.
the object is speeding up.
the object is slowing down.

1. choose the best answer.

what does a slanted straight line sloping up on a distance - time graph represent?
the object is speeding up.
the object is not moving.
the object is moving at a constant speed.
the object is slowing down.

1. choose the best answer.

what does a curved line sloping down on a distance - time graph represent?
an object is moving back toward the starting point and slowing down.
an object is moving back toward the start point and at a constant speed.
an object is moving away from the starting point and speeding up.
an object is moving away from the starting point at a constant speed.

Explanation:

1. A distance - time graph is designed to show how the distance of an object changes over time, so the first answer is based on its fundamental purpose.
2. The slope of a line on a distance - time graph is calculated as $\frac{\text{change in distance}}{\text{change in time}}$, which is the definition of speed.
3. A horizontal line means the distance is not changing as time progresses, so the object is not moving.
4. A slanted straight line sloping up indicates a constant positive rate of change of distance with respect to time, meaning the object is moving at a constant speed.
5. A curved line sloping down shows the object is moving back towards the starting point (decreasing distance) and the curve indicates the speed is changing in a way that it is slowing down.

Answer:

1. to show the relationship between an object's distance and time
2. speed at which an object is traveling
3. The object is not moving.
4. The object is moving at a constant speed.
5. An object is moving back toward the starting point and slowing down.