# Does luminosity depend on distance?

## Does luminosity depend on distance?

The difference between luminosity and apparent brightness depends on distance. ... If you put an automobile headlight 10 feet away and a flashlight 10 feet away, the flashlight will appear fainter because its luminosity is smaller. Stars have a wide range of apparent brightness measured here on Earth.

## Do lights in equal distance away from you have the same brightness?

The intensity or brightness of light as a function of the distance from the light source follows an inverse square relationship. ... Notice that as the distance increases, the light must spread out over a larger surface and the surface brightness decreases in accordance with a "one over r squared" relationship.

## How is apparent brightness calculated?

Apparent brightness is thus measured in watts per square meter. For instance, the apparent brightness of the Sun is b = 1370 watts/meter2. That is, if you had a perfectly efficient solar panel one meter on a side, if you held it perpendicular to the Sun's rays, it would generate 1370 watts of electricity.

## Why does light get dimmer with distance?

Light gets dimmer with distance based on the inverse square law. This means that because an object does not give off, or reflect an infinite number of photons, the further away from the source an observer gets, the greater the ratio of space per photon.

## How do we calculate distance to stars?

1. Trigonometric Parallax method determines distance to star or other object by measuring its slight shift in apparent position as seen from opposite ends of Earth's orbit. ( ...
2. Astronomers use a technique called parallax to precisely measure to distance to stars in the sky.

Red stars

## How is galaxy distance calculated?

To determine the distance to a galaxy one would only need to measure its apparent (angular) size, and use the small angle equation: a = s / d, where a is the measured angular size (in radians!), s is the galaxy's true size (diameter), and d is the distance to the galaxy.

## How do you calculate the distance?

The formula can be rearranged in three ways:

1. speed = distance ÷ time.
2. distance = speed × time.
3. time = distance ÷ speed.

## What is the formula for shortest distance?

Using the Distance Formula , the shortest distance between the point and the circle is |√(x1)2+(y1)2−r | .

## How do you find distance on a graph?

Simply subtract the x-values and the y-values to find the lengths. Therefore, if we were to plug in the points of (x1, y1), and (x2, y2), then move the square over to the other side of the equation so that it becomes a square root, we'll get the formula for distance.

## How do you find distance on a graph in physics?

Calculating the distance travelled

1. Calculate the total distance travelled by the object - its motion is represented by the velocity-time graph below.
2. Here, the distance travelled can be found by calculating the total area of the shaded sections below the line.
3. ½ × base × height.
4. ½ × 4 × 8 = 16 m 2
5. (10 – 4) × 8 = 48 m 2

## How can the shortest distance between 2 points be a curve?

The shortest distance between two points is a straight line. Parallel lines never meet. On a curved surface, like a globe: The shortest distance between two points is a curved line (on a spherical globe, the shortest distance is a great circle).

## What is the straightest possible line?

However, a straight line is only the shortest distance between two points on a flat surface....Curved Space

• - Speed of Light and the Principle of Relativity.
• - Special Theory of Relativity.
• - Space-Time.
• - E = mc. ...
• - Gravity and Acceleration.
• - Curved Space.
• - General Theory of Relativity.
• - Conclusion.

## Why is the shortest distance between two points a straight line?

So, if we define a straight line to be the one that a particle takes when no forces are on it, or better yet that an object with no forces on it takes the quickest, and hence shortest route between two points, then walla, the shortest distance between two points is the geodesic; in Euclidean space, a straight line as ...

Eyre Highway

## What is the longest line in the world?

Darryl Learie drew a chalk line 8,067.

## What's the longest stretch of land?

Did you know which two points on Earth have the longest distance in a straight line? Guy Bruneau, a wild cartographer at Google has come up with a map that shows the longest-possible straight land path on Earth to walk upon. The line starts at about 10 km north of Greenville, Liberia, and ends near Wenling, China.