1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
olya-2409 [2.1K]
3 years ago
7

Where does the name "Black Hole" get it's name?

Physics
2 answers:
jenyasd209 [6]3 years ago
8 0

nothing escapes them not even light therefore they are (dark) and  we see them be literally black holes
Vikentia [17]3 years ago
4 0
The "Black Hole" gets its name from the astronomical amount of gravitational force created by the black hole. This gravitational force is so great that even light cannot escape it, hence, it is completely black
You might be interested in
an astronaut on an eva has wandered dangerously far away from the shuttle. she has also exhausted all the fuel in her jet pack.
V125BC [204]

The conservation of the momentum allows to find the result of how the astronaut can return to the spacecraft is:

  • Throwing the thruster away from the ship.

The momentum is defined as the product of the mass and the velocity of the body, for isolated systems the momentum  is conserved. If we define the system as consisting of the astronaut and the evo propellant, this system is isolated and the internal forces become zero. Let's find the moment in two moments.

Initial instant. Astronaut and thrust together.

        p₀ = 0

Final moment. The astronaut now the thruster in the opposite direction of the ship.

       m_f = m v + M v '

where m is propellant mass and M the astronaut mass.

As the moment is preserved.

       0 = m v + M v ’

      v ’= - \frac{m}{M} \ v  

We can see that the astronaut's speed is in the opposite direction to the propeller, that is, in the direction of the ship.

The magnitude of the velocity is given by the relationship between the masses.

In conclusion, using the conservation of the momentun we can find the result of how the astronaut can return to the ship is:

  • Throwing the thruster away from the ship.

Learn more here:  brainly.com/question/14798485

5 0
2 years ago
As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff ideal sprin
shepuryov [24]

Answer:

The magnitude of force must you apply to hold the platform in this position = 888.89 N

Explanation:

Given that :

Workdone (W) = 80.0 J

length x = 0.180 m

The equation  for this  work done by the spring is expressed as:

W = \frac{1}{2}k_{eq}x^2

Making the spring constant k_{eq} the subject of the formula; we have:

k_{eq} = \frac{2W}{x^2}

Substituting our given values, we have:

k_{eq} = \frac{2*80}{0.180^2}

k_{eq} = 4938.27 \ N.m^{-1}

The magnitude of the force that must be apply  to the hold platform in this position is given by the formula :

F = k_{eq}x

F = 4938.27*0.180

F = 888.89 N

6 0
3 years ago
Find the change in kinetic energy of a 0.650 kg fish leaping to the right at 15.0 m/s that collides inelastically with a 0.950 k
yaroslaw [1]
The change in the kinetic energy refers to the work done in displacing a body, thus, the change in the kinetic energy of an object refers to the work done on the object.
The correct formula to use is:
W = Initial kinetic energy - Final kinetic energy;
Where, W = change in kinetic energy
Final kinetic energy and initial kinetic energy = 1/2 MV^2
Initial velocity = 15 m/s
Final velocity  = 13.5 m/s
Initial mass = 0.650 kg
Final mass = 0.950 kg
W = 1/2 [0.650* (15 *15)] - 1/2 [0.950 * (13.5 * 13.5)]
W = 146.25 - 173.13 = 26.88
Therefore, the change in kinetic energy is 26.88 J.
 The negative sign has to be ignored, because change in kinetic energy can not be negative.
<span />
4 0
3 years ago
Read 2 more answers
Cooling down after a workout allows the oxygen to continuing moving through the body and keeps the muscles from tightening up to
Liono4ka [1.6K]

Answer: true

Explanation:

7 0
3 years ago
Read 2 more answers
A cube of water 10 cm on a side is placed in a microwave beam having Ea = 11 kV/m‘ The microwaves illuminate one faceofthe cube,
Shtirlitz [24]

Answer:

The time is 133.5 sec.

Explanation:

Given that,

One side of cube = 10 cm

Intensity of electric field = 11 kV/m

Suppose How long will it take to raise the water temperature by 41°C Assume that the water has no heat loss during this time.

We need to calculate the rate of energy transfer from the beam to the cube

Using formula of rate of energy

P=(0.80)IA

P=0.80\times\dfrac{c\mu_{0}E^2}{2}\times A

Put the value into the formula

P=0.80\times\dfrac{3\times10^{8}\times8.85\times10^{-12}\times(1.1\times10^{4})^2}{2}\times(10\times10^{-2})^2

P=1285.02\ W

We need to calculate the amount of heat

Using formula of heat

E =mc\Delta T

E =\rho Vc\Delta T

Put the value into the formula

E=1000\times(0.10)^3\times4186\times41

E=171626\ J

We need to calculate the time

Using formula of time

t=\dfrac{E}{P}

Put the value into the formula

t=\dfrac{171626}{1285.02}

t=133.5\ sec

Hence, The time is 133.5 sec.

3 0
4 years ago
Other questions:
  • 300 g2 divide by 0.0005 g in scientific notation
    13·1 answer
  • Do you think distance and time are relevant terms in describing motion?
    9·2 answers
  • What is the meaning of heredity
    11·1 answer
  • What is the net force when forces applied are 300 N to the right and 100 N to the right
    8·1 answer
  • I’m tryna pass this class so pleaseee
    11·1 answer
  • A sprinter practicing for the 200-m dash accelerates uniformly from rest at A and reaches a top speed of 35 km/h at the 67-m mar
    10·1 answer
  • If a 5 kg bowling ball is lifted to a height of 2 meters, how much potential
    12·1 answer
  • Haha jk thats really funny that it doesnt let you take down questions
    5·2 answers
  • When you serve the ball, if the ball does not land in the opposite side rectangle this is called a ______. question 2 options: f
    13·1 answer
  • Acceleration can occur when a car is moving at a constant speed. what must cause this acceleration?​
    12·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!