All categories

3 years ago

When making maps of the large-scale universe, astronomers estimate distances to the vast majority of galaxies by using:

Physics

1 answer:

Vesnalui [34]3 years ago

4 0

Answer:

The comoving distance and the proper distance scale

Explanation:

The comoving distance scale removes the effects of the expansion of the universe, which leaves us with a distance that does not change in time due to the expansion of space (since space is constantly expanding). The comoving distance and proper distance are defined to be equal at the present time; therefore, the ratio of proper distance to comoving distance now is 1. The scale factor is sometimes not equal to 1. The distance between masses in the universe may change due to other, local factors like the motion of a galaxy within a cluster. Finally, we note that the expansion of the Universe results in the proper distance changing, but the comoving distance is unchanged by an expanding universe.

You might be interested in

A jogger moves from a position x =

vlada-n [284]

Answer:

3 m/s

Explanation:

We'll begin by calculating the change in displacement of the jogger. This can be obtained as follow:

Initial displacement (d₁) = 4 m

Final displacement (d₂) = 16 m

Change in displacement (Δd) =?

Δd = d₂ – d₁

Δd = 16 – 4

Δd = 12 m

Finally, we shall determine the determine the average velocity. This can be obtained as follow:

Change in displacement (Δd) = 12 m

Time (t) = 4 s

Velocity (v) =?

v = Δd / t

v = 12 / 4

v = 3 m/s

Thus, the average velocity of the jogger is 3 m/s

5 0

3 years ago

Which of these terms means an object's resistance to changing its motion?

Mila [183]

Answer:

Inertia

F=ma

Action, reaction

All of the above

A heavy object requires more force to push than a lighter object.

8 0

2 years ago

Why does a gymnast rub powder on his hands before exercising on a set of parallel bars? (I need a scientific answer)

dlinn [17]

Answer

To increase friction for a better grip.

Answer

Most human beings do sweat hands especially on the palm. When this happens the person will not have a good grip of heavy objects because they will slide/slip from the hand.

By applying the powder, you are trying to make the hand dry hence increasing the friction for a better grip.

If the gymnast doesn't do this the parallel bars may slip from the hands and injure himself or herself.

4 0

2 years ago

Read 2 more answers

Explain why 15yr old need more calcium than adults

Tom [10]

Answer:

When adolescents get enough calcium during the teen years, they can start out their adult lives with the strong bones and significantly reduce their risk for fractures as an adult. Inadequate calcium intake during adolescence and young adulthood puts individuals at risk for developing osteoporosis later in life.

8 0

3 years ago

Read 2 more answers

You are helping your friend move a new refrigerator into his kitchen. You apply a horizontal force of 252 N in the negative x di

pentagon [3]

(a) 252 N, opposite to the applied force

There are two forces acting on the refrigerator in the horizontal direction:

- the pushing force of 252 N, F, forward

- the frictional force, Ff, pulling backward

In this case, the refrigerator is not moving: this means that its acceleration is zero. According to Newton's second law, this also means that the net force acting on the refrigerator is also zero:

$\sum F = ma = 0$