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
valkas [14]
3 years ago
8

Astronomers have proposed the existence of an unexplained force that is causing the expansion of the universe to accelerate. Wha

t do they call this force?
dark matter
dark space
dark stars
dark energy
dark holes
Physics
2 answers:
Hoochie [10]3 years ago
6 0
<h3><u>Answer;</u></h3>

Dark matter

<h3><u>Explanation;</u></h3>
  • <em><u>Astronomers theorize that the faster expansion rate is due to a mysterious, dark force that is pulling galaxies apart. One explanation for dark energy is that it is a property of space.</u></em>
  • Space has amazing properties, many of which are just beginning to be understood.
  • Another explanation for dark energy is that it is a new kind of dynamical energy fluid or field. Dark matter makes up about 27%.
Alik [6]3 years ago
4 0
4. Dark Energy. This is the mysterious force causing the expansion of space. No one has ever seen this force.
You might be interested in
A soccer field is viewed from above, while a ball is kicked eastward with an initial speed of 10.0 m/s. The ball experiences a c
satela [25.4K]

Answer:

the ball travelled approximately 60 m towards north before stopping

Explanation:

 Given the data in the question;

First course : a_{x} = 0.75 m/s², d_{x} = 20 m, u_{x} = 10 m/s

now, form the third equation of motion;

v² = u² + 2as

we substitute

v_{x}² = (10)² + (2 × 0.75 × 20)

v_{x}² = 100 + 30

v_{x}² = 130

v_{x} = √130

v_{x} = 11.4 m/s

for the Second Course:

u_{y} =  11.4 m/s,  a_{y} = -1.15 m/s²,  v_{y} = 0

Also, form the third equation of motion;

v² = u² + 2as

we substitute

0² = (11.4)² + (2 × (-1.15) ×  d_{y} )

0 = 129.96 - 2.3d_{y}

2.3d_{y}  = 129.96

d_{y} = 129.96 / 2.3

d_{y} = 56.5 m

so;

|d| = √( d_{x}² + d_{y}² )

we substitute

|d| = √( (20)² + (56.5)² )

|d| = √( 400 + 3192.25 )

|d| = √( 3592.25 )

|d| = 59.9 m ≈ 60 m

Therefore, the ball travelled approximately 60 m towards north before stopping

7 0
3 years ago
The emf induced in a coil that is rotating in a magnetic field will be at a maximum at which moment?
adelina 88 [10]
TLDR: It will reach a maximum when the angle between the area vector and the magnetic field vector are perpendicular to one another.

This is an example that requires you to investigate the properties that occur in electric generators; for example, hydroelectric dams produce electricity by forcing a coil to rotate in the presence of a magnetic field, generating a current.

To solve this, we need to understand the principles of electromotive forces and Lenz’ Law; changing the magnetic field conditions around anything with this potential causes an induced current in the wire that resists this change. This principle is known as Lenz’ Law, and can be described using equations that are specific to certain situations. For this, we need the two that are useful here:

e = -N•dI/dt; dI = ABcos(theta)

where “e” describes the electromotive force, “N” describes the number of loops in the coil, “dI” describes the change in magnetic flux, “dt” describes the change in time, “A” describes the area vector of the coil (this points perpendicular to the loops, intersecting it in open space), “B” describes the magnetic field vector, and theta describes the angle between the area and mag vectors.

Because the number of loops remains constant and the speed of the coils rotation isn’t up for us to decide, the only thing that can increase or decrease the emf is the change in magnetic flux, represented by ABcos(theta). The magnetic field and the size of the loop are also constant, so all we can control is the angle between the two. To generate the largest emf, we need cos(theta) to be as large as possible. To do this, we can search a graph of cos(theta) for the highest point. This occurs when theta equals 90 degrees, or a right angle. Therefore, the electromotive potential will reach a maximum when the angle between the area vector and the magnetic field vector are perpendicular to one another.

Hope this helps!
6 0
3 years ago
Two different liquids are poured into a jar until it is half full. The jar is then sealed shut and shaken. The liquids undergo a
Lilit [14]

Answer:

A closed system.

Explanation:

The three major types of system are: open, closed and isolated. Open system interacts with its surroundings with respect to its particles and energy. A closed system interacts with its surroundings with respect to energy but not its particles. While an isolated system does not interact with its surroundings in any way.

Therefore, after the jar is sealed, it is an example of a closed system. This is because the emitted gas could not escape into the surroundings, but thermal energy was emitted into its surroundings after the chemical reaction has taken place.

7 0
3 years ago
Two identical cars, one on the moon and one on the earth, have the same speed and are rounding banked turns that have the same r
Naily [24]

Answer:

The value of the centripetal forces are same.

Explanation:

Given:

The masses of the cars are same. The radii of the banked paths are same. The weight of an object on the moon is about one sixth of its weight on earth.

The expression for centripetal force is given by,

F_{c} = \dfrac{mv^{2}}{r}

where, m is the mass of the object, v is the velocity of the object and r is the radius of the path.

The value of the centripetal force depends on the mass of the object, not on its weight.

As both on moon and earth the velocity of the cars and the radii of the paths are same, so the centripetal forces are the same.

3 0
3 years ago
Dont use me for points please i need help, (circuits for physics)
zhannawk [14.2K]

Answer:

B, A, A, B

Explanation:

Just trust me on this one.

3 0
2 years ago
Other questions:
  • Modern scientists say that electrons are found in a ...
    6·2 answers
  • What is the element with 107 electrons
    15·2 answers
  • The speed of light is about 3.00 × 105 km/s. It takes approximately 1.28 seconds for light reflected from the
    14·1 answer
  • Which planet has a rocky mantle, iron core and very dense atmosphere that is 96.5% poisonous carbon dioxide and 3.5% nitrogen?
    11·2 answers
  • Short answer
    8·1 answer
  • A high-speed K0 meson is traveling at β = 0.90 when it decays into a π + and a π − meson. What are the greatest and least speeds
    6·1 answer
  • What is the mass of an object Destiny is 4 grams / milliliters and its volume is 8 ml​
    6·1 answer
  • A plane that is 2000m in the air of the potential energy of the plane is 86000 J what is the mass of the plane
    5·1 answer
  • What are three examples of noncontact forces​
    13·1 answer
  • Which scenario presents a possible environmental impact due hydrogen fuel cells?
    6·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!