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3 years ago

Describe the main distinguishing features of spiral, elliptical, and irregular galaxies.

Physics

1 answer:

hram777 [196]3 years ago

5 0

Answer:

Spiral galaxies consist of a flat, rotating disk of stars, gas and dust, and a central concentration of stars known as the bulge. These are surrounded by a much fainter halo of stars, many of which reside in globular clusters.

Elliptical galaxies have smooth, featureless light-profiles and range in shape from nearly spherical to highly flattened, and in size from hundreds of millions to over one trillion stars. In the outer regions, many stars are grouped into globular clusters. Most elliptical galaxies are composed of older, low-mass stars, with a sparse interstellar medium and minimal star formation activity They are often chaotic in appearance, with neither a nuclear bulge nor any trace of spiral arm structure. Collectively they are thought to make up about a quarter of all galaxies.

irregular galaxies were once spiral or elliptical galaxies but were deformed by gravitational action. they are shapeless.

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How far will a car travel if its velocity is 15 m/s in 3 seconds? Follow example below.

svet-max [94.6K]

<h3>Solution:</h3>

Distance (d) = 112 m
Time (t) = 4 seconds
Let the speed be v.
We know, speed = Distance / Time
Therefore, v = d/t

or, v = 112 m ÷ 4 s = 28 m/s

<h3>Answer:</h3>

The speed of the cheetah is 28 m/s.

4 0

2 years ago

On a playground, there is a merry‑go‑round. In order to get it moving, Bonnie applies a force of 31 N31 N . The merry‑go‑round m

nika2105 [10]

Answer:

The magnitude of the torque is 263.5 N.

Explanation:

Given that,

Applied force = 31 N

Distance from the axis = 8.5 m

She applies her force perpendicularly to a line drawn from the axis of rotation

So, The angle is 90°

We need to calculate the torque

Using formula of torque

$\tau=Fd\sin\theta$

Where, F = force

d = distance

Put the value into the formula

$\tau=31\times8.5\sin90$

$\tau= 263.5\ N$

Hence, The magnitude of the torque is 263.5 N.

4 0

3 years ago

A steel bar of rectangular cross section (1.5 in. 2 3 .0 in.) carries a tensile load P (see fig- ure). The allowable stresses in

lukranit [14]

Explanation:

Value of the cross-sectional area is as follows.

A = $1.5 \times 2.30$

= 3.45 $in^{2}$

The given data is as follows.

Allowable stress = 14,500 psi

Shear stress = 7100 psi

Now, we will calculate maximum load from allowable stress as follows.

$P_{max} = \sigma_{a}A$

= $14500 \times 3.45$

= 50025 lb

Now, maximum load from shear stress is as follows.

$P_{max} = 2 \times \tau_{a} \times A$

= $2 \times 7100 \times 3.45$

= 48990 lb

Hence, $P_{max}$ will be calculated as follows.

$P_{max} = min((P_{max})_{\sigma}, (P_{max})_{\tau})$

= 48990 lb

Thus, we can conclude that the maximum permissible load $P_{max}$ is 48990 lb.

4 0

3 years ago

I need help ASAP I need to get this right plz plz plz!!!!!

Rina8888 [55]

The atomic nucleus consists of protons and neutrons.

Additional information:

Protons are positively charged particle and neutrons are negatively charged particle.

Hope this will help u...:)

3 0

3 years ago

Read 2 more answers

How are the energy conversions of machines similar to the energy conversions in your body

sleet_krkn [62]

Answer:

Explained below

Explanation:

When we eat food, our body gets chemical energy from it. Now, this chemical energy from the food is changed into some different energy forms that is useful to it. They include:

-Chemical to mechanical energy to aid in movement of muscles

- chemical to thermal energy to aid in regulating the body temperature.

- chemical to electrical energy to aid the brain in thinking.

Thus is similar to how a machine converts energy because machines also generate energy after being powered and convert to other forms of energy. For example, an alarm clock converts electrical energy to sound energy, hair dryer converts electrical energy to thermal/heat energy.

6 0

3 years ago