Question

The speed is represented by

Answer 1

Answer:

The absolute value of the slope of a position-time graph.

Explanation:

The slope in a time position graph is the derivative of the position with respect to time.

This derivative of the position with respect to time is what is known as velocity, which is a vector quantity.

Speed is the absolute value of velocity, since it is a scalar quantity, it has no sign and no direction.

So the correct answer is that speed is the absolute value of the slope in a graph of position and time.

Answer 2

Answer:

Instantaneous velocity is equal to speed of the object at that particular instant.

Explanation:

Instantaneous velocity is the velocity of the object at that particular instant. It is also equal to speed of the object at that instant. It can be calculated by drawing a tangent to the position-time graph at that point and finding the tangent’s slope.

The first option ‘The ratio of change in position to the time interval during that change’  gives the average velocity of an object and not speed. Similarly the second option ‘the absolute value of the slope of position time graph’ gives the average speed.