All categories

3 years ago

What do we mean by the event horizon of a black hole?

Physics

2 answers:

TEA [102]3 years ago

5 0

<h2>Answer:</h2>

The event horizon is the surface of a black hole, it is the border of space-time in which the events on one side of it can not affect an observer on the other side.

That is, at this border also called "point of no return", nothing can escape (not even light) and no event that occurs within it can be seen from outside.

Flura [38]3 years ago

3 0

Answer:

The event horizon is an imaginary surface surrounding a black hole, where the escape velocity is equal to the speed of light. Therefore, nothing within that horizon can escape due to the attraction of a large gravitational field

Explanation:

No particle that falls within the event horizon comes out again, since a speed greater than light would be needed, and so far no particle can reach it. In this way, there is no way to look inside the event horizon. For this reason, black holes have no visible characteristics.

You might be interested in

PLEASEEE HELPPPP

solniwko [45]

Answer:

Explanation:

average speed more than 25.0m/s.

5 0

2 years ago

Read 2 more answers

The left end of a long glass rod 8.00 cm in diameter, with an index of refraction 1.60, is ground to a concave hemispherical sur

sp2606 [1]

Answer:

a) q = -9.23 cm, b) h’= 0.577 mm , c) image is right and virtual

Explanation:

This is an optical exercise, where the constructor equation should be used

1 / f = 1 / p + 1 / q

Where f is the focal length, p the distance to the object and q the distance to the image

A) The cocal distance is framed with the relationship

1 / f = (n₂-1) (1 /R₁ -1 /R₂)

In this case we have a rod whereby the first surface is flat R1 =∞ and the second surface R2 = -4 cm, the sign is for being concave

1 / f = (1.60 -1) (1 /∞ - 1 / (-4))

1 / f = 0.6 / 4 = 0.15

f = 6.67 cm

We have the distance to the object p = 24.0 cm, let's calculate

1 / q = 1 / f - 1 / p

1 / q = 1 / 6.67 - 1/24

1 / q = 0.15 - 0.04167 = 0.10833

q = -9.23 cm

distance to the negative image is before the lens

B) the magnification of the lenses is given by

M = h ’/ h = - q / p

h’= - q / p h

h’= - (-9.23) / 24.0 0.150

h’= 0.05759 cm

h’= 0.577 mm

C) the object is after the focal length, therefore, the image is right and virtual

6 0

3 years ago

A red blood cell is 7 x 10-6 m in size. This means it is 7 __________ in size. What unit completes the sentence?

aalyn [17]

If a red blood cell is 7 x $10^-^6$ m in size, it means that such a cell is 7 microns or micrometer in size. The unit that completes the sentence will, thus, be microns or micrometer.

According to international system of measurement:

$10^{-1}$ m = decimeter

$10^{-2}$ m = centimeter

$10^{-3}$ m = millimeter
$10^{-6}$ m = micrometer or micron
$10^{-9}$ m = nanometer

Thus, a measurement of 7 x $10^-^6$ m is the same is 7 micons or 7 micrometer.

More on metric conversion can be found here: brainly.com/question/17767575

5 0

1 year ago

It is correct to say that impulse is equal toA) momentum.B) the change in momentum.C) the force multiplied by the distance the f

Elena-2011 [213]

Answer:

B) the change in momentum.

Explanation:

The impulse is defined as the product between the force applied on an object (F) and the duration of the collision ( $\Delta t$ ):

$J=F \Delta t$ (1)

We can rewrite the force by using Newton's second law, as the product between mass (m) and acceleration (a):

$F=ma$

So, (1) becomes

$J=ma \Delta t$

Now we can also rewrite the acceleration as ratio between the change in velocity and change in time: $a=\frac{\Delta v}{\Delta t}$ . If we substitute into the previous equation, we find