Question

A student writes, "A bird that is diving for prey has a speed of −10m/s." What is wrong with the student’s statement? What has the student actually described? Explain.

a) The student described the bird's velocity, not speed.

b) The student's statement is accurate.

c) The student confused acceleration with speed.

d) The student described the bird's displacement.

Answer 1

The student erroneously described velocity as speed; speed is always positive, whereas velocity, being a vector, includes direction and can be negative.

Step-by-step explanation:

The student's statement "A bird that is diving for prey has a speed of -10 m/s" is incorrect because speed is a scalar quantity, which means it does not have a direction and is always positive. The student has actually described the bird's velocity, which is a vector quantity and can have a negative value indicating direction. Therefore, the correct answer is: a) The student described the bird's velocity, not speed.

Acceleration is the change in velocity over time and, since it involves both a magnitude and a direction, it is also a vector quantity.