Question

Which of the following statements does NOT use the term angular size or angular distance correctly?

choices:

1. The angular distance between those two bright stars in the sky is about 2 meters.
2. You can use your outstretched hand against the sky to estimate angular sizes and angular distances.
3. The angular size of the Sun is about the same as that of the Moon.
4. The angular distance between those two houses in the distance is 30 degrees.

Answer 1

Answer: Statement 1 is incorrect.

Reason:

Unit of measure of angular distance is not meters.

Step-by-step explanation:

The term 'angular size' is used to describe the apparent size of the objects in the night sky.

The angular distance is defined as the angle through which an object moves on a circular path. The SI unit is radian.

Other units are revolution (rev) and degrees.

In statement 1, angular distance is measured in meters which is incorrect. In other options, there is no factual mistake so they are correct.

Let's discuss them,

Statement 2:

Here, we are talking about the use of outstretched hand to estimate the angular distances and sizes which is correct.

Statement 3:

This statement talks about the same angular sizes of the sun and the moon, here the term is again used correctly.

Statement 4:

Here, the angular distance is measured in the correct units i.e, degrees so this statement is also correct.