Question

Let the speed of an object falling from a certain height be given by the equation $y=10x$, where $x$ indicates time. Which of the following is(are) true?

• A. 10 is the constant of proportionality
• B. As time increases , speed decreases
• C. Speed and time are proportional.
• D. Speed and time are not proportional.

Answer 1

Answer: (A), (C)

The correct options are
A

10 is the constant of proportionality

C

Speed and time are proportional.

Given that $y=10x$, where $x$ indicates time and $y$ indicates speed. Thus, we have $y$ and $x$ to be directly proportional and the constant of proportionality is 10. In other words, as time increases, so does the speed.