What would most likely cause the future acceleration of the expansion of the universe
Radiation
The existence of background radiation
Light shifts identified by Doppler effect

Answers

Answer 1

Answer:

never scared

that might help you


Related Questions

A ball is thrown vertically upward with a speed v. An identical second ball is thrown upward with a speed of 1/2 v (half as fast). What is the ratio of the maximum height of the second ball to that of the first ball

Answers

Answer:

1:4

Explanation:

The formula for calculating the maximum height of the ball is expressed as;

H = u²sin²theta/2g

If a ball is thrown vertically upward with a speed v, its maximum height is expressed as;

H = v²sin²90/2g

Since sin90 = 1

H = v²/2g.... 1

If an identical second ball is thrown upward with a speed of 1/2 v, then the maximum height will be expressed as;

H1 = (1/2v)²sin²90/2g

H1 = (v²/4)(1)/2g

H1 = v²/8g ...... 2

Divide both equations

H/H1 = (v²/2g)/(v²/8g)

H/H1 = v²/2g × 8g/v²

H/H1 = 8g/2g

H/H1 = 4

Reciprocate both sides

H1/H = 1/4

H1:H = 1:4

Hence the ratio of the maximum height of the second ball to that of the first ball is 1:4

what does the area under a speed-time graph represent​

Answers

Answer: It represents the whole distance traveled. Hope this helps!

Explanation:

Water boiling

Which one is shown? (Look at pic)

Answers

Answer:

conduction.

Explanation:

Hoped I helped! Im Eve btw have a great day and consider marking this brainliest if you do thank you in advanced!

a student tries to produce notes of higher frequency by blowing a trumpet harder. he will succeed?​

Answers

Answer:

Please mark as Brainliest!!

Explanation:

He will not succeed as it blows the trumpet harder that only increase the amplitude of the sound wave that means the intensity of the sound will increase but the frequency remains the same.

Answer:

he wont

Explanation:

Where could we use a light bulb that has 12V written on it

Answers

Answer:

Explanation:

In a battery charger (for an auto).

As a replacement for any bulb in an auto.

As a lamp in an emergency exit where the power must be shut off.

As a light that illuminates the back of a truck, turned on when loading the truck.

PLEASE HELP ME this is due in 20 mins!!!!!
See how a block and tackle system can increase your mechanical advantage. You will need two broomsticks, a rope, and two helpers.

A. Give each helper a broom stick and have them stand facing each other holding the broomstick firmly in both hands in a horizontal position. The broomsticks should be at the same level, about two feet apart.

B. Tie one end of the rope to one of the broomsticks. (You may need to have one of your helpers hold the knot firmly in one hand as he or she holds the broomstick to help anchor it.)

C. Wrap the rope around the other broomstick, as in a simple pulley system, and pull on the free end of the rope. Your helpers should resist your pulling. What happens? Can you pull the broomsticks together?

D. Now weave the rope back over the first broomstick, so you have a double pulley. Pull on the free end. What happens now? Can you pull the broomsticks together? What is your mechanical advantage?

E. Try weaving the rope over the broomsticks one or two more times. Describe what happens, and state the mechanical advantage of each situation.

F. Write a summary of what happened and an explanation using the terms:

force
distance
work
mechanical advantage

Answers

The mechanical advantage of using this pulley system is equal to the amount of force used on the broomsticks. I used work times distance and the total distance was 15. I hope I answered this right lol!

The ball as launched horizontally off a 200m cliff. The initial velocity is 40m/s.
Find the time it takes to hit the ground.
Find the RANGE, distance traveled horizontally.
Find the final vertical velocity.

Answers

Answer:

a. 6.39 s b. 255.6 m c. 62.6 m/s

Explanation:

a. Find the time it takes to hit the ground.

Using y = ut + 1/2gt² where y = height of cliff = 200 m, u = initial vertical velocity of ball = 0 m/s, g = acceleration due to gravity = 9.8 m/s² and t = time taken for ball to hit the ground.

So, substituting the values of the variables into the equation, we have

200 m = 0 m/s × t + 1/2 × 9.8 m/s² × t²

200 m = 0 + (4.9 m/s²)t²

200 m = (4.9 m/s²)t²

dividing both sides by 4.9 m/s², we have

t² = 200 m ÷ 4.9 m/s²

t² = 40.82 s²

taking square root of both sides, we have

t = √(40.82 s²)

t = 6.39 s

b. Find the RANGE, distance traveled horizontally.

The range is the horizontal distance traveled by the ball, R = vt where v = horizontal velocity of ball = 40 m/s and t = time taken for ball to hit the ground = 6.39 s

So, R = vt

= 40 m/s × 6.39 s

= 255.6 m

c. Find the final vertical velocity.

Using v = u - gt where u = initial vertical velocity of ball = 0 m/s, v = final velocity of ball, g = g = acceleration due to gravity = 9.8 m/s² and t = time taken for ball to hit the ground = 6.39 s.

So, substituting the values into the equation, we have

v = 0 m/s - 9.8 m/s² × 6.39 s

v = -62.62 m/s

v ≅ -62.6 m/s

The pitch of a sound is most closely related to what ?

Answers

It’s related to sound frequency! Hope this helps!

A 43 kg box is being pushed and pulled by
three forces. The first force is 155 N to the
right. The second force is 227 N to the left.
The third force is 113 N to the right. What is
the acceleration of the box?

Answers

Answer:

a = - 0.209 [m/s²]

Explanation:

To solve this problem we must use Newton's second law which tells us that the sum of forces on a body is equal to the product of mass by acceleration.

∑F = m*a

We will take the positive forces to the right and the negative forces to the left.

[tex]155-277+113=43*a\\-9=43*a\\a = - 0.209[m/s^{2} ][/tex]

The negative sign means that the box accelerates in a negative direction to the left.

Clarissa has a credit card with a limit of $1,000 and pays her balance in full each month. If Clarissa needs a short-term loan, can she use her credit card as collateral at a pawn shop? Why or why not? Select the best answer from the choices provided. A. She cannot use it because a credit card is not collateral. B. If the balance on the credit card is zero, she can use it. C. If the balance on the credit card is $1,000, she cannot use it. D. She can use it if she increases the credit limit.

Answers

Answer:

B.she cannot use it because the credit card is not collareral

Explanation:

sorry if am wrong

Which term below best matches this definition - a period in European history when many educated people stressed the importance of learning and reasoning; education was considered the key to understanding and solving society's problems

Answers

Answer:

The Enlightenment.

Explanation:

The Enlightenment took place during the eighteen century and it typically involved a period of philosophical, cultural and intellectual movement in which ideas on nature, reason, humanity and God were emphasized on greatly over science and superstition through meetings that were held at coffeeshops, scientific academies, literary salons, masonic lodges, etc. Some of the influential philosophers of the enlightenment were Adam Smith, John Locke, Jean Jacques Rousseau, David Hume, Baruch Spinoza, Montesquieu, Hugo Grotius, Denis Diderot, Gottfried Wilhelm, Cesare Beccaria, Immanuel Kant etc. The enlightenment was also known as the age of reason or the age of enlightenment.

Hence, the enlightenment was a period in European history when many educated people stressed the importance of learning and reasoning; education was considered the key to understanding and solving society's problems.

if a quarterback applies a 100N force on a football for a distance of .5m, how much work does he do on the ball


PLEASE HELP

Answers

Explanation:

Work done = F * d = 100N * 0.5m = 50J.

John wants a new video tape and a new shirt, but he only has $12.00. He buys the video tape and gets $0.52 change. What was his opportunity cost?

Answers

Answer:

You have the answer in your comments. I will be copying it so your question doesn't get deleted.

The answers is $0.58

$11.48

the video tape

the new shirt

Please help I will send pics in return or I will mark brainliest (depending on what u want) for a good attempt and explanation.

Answers

The answer would have to be 8.47 m/s/s because the backwards pull + the rate of speed it is going would have to be added to get the answer to compensate for the backwards pull

Why is it difficult to use the law of conservation of energy to calculate the
effects of a collision?

Answers

Answer:

B

Explanation:

In a collision some of the kinetic energy of the object convert into thermal energy and sound. It's not so easy to measure thermal and sound energy. That's why it's difficult to use law of conservation of energy.

Alert: Energy is always conserved.

I NEED THE ANSWER ASAP

A sled accelerates to the right with a value of 10 m/s^2. There is a force acting to the left the is 80 N. If the mass of the sled is 40 kg, what must be the force acting to the right?

Answers

Answer:

m/s^-30

Explanation:

An unknown material, m1 = 0.41 kg, at a temperature of T1 = 86 degrees C is added to a Dewer (an insulated container) which contains m2 = 1.7 kg of water at T2 = 22 degrees C. Water has a specific heat of cw = 4186 J/(kg⋅K). After the system comes to equilibrium the final temperature is T = 30.3 degrees C.

Answers

Complete Question

An unknown material, m1 = 0.41 kg, at a temperature of T1 = 86 degrees C is added to a Dewer (an insulated container) which contains m2 = 1.7 kg of water at T2 = 22 degrees C. Water has a specific heat of cw = 4186 J/(kg⋅K). After the system comes to equilibrium the final temperature is T = 30.3 degrees C.

Part (a) Input an expression for the specific heat of the unknown material.

Part (b) What is the specific heat in J/(kg⋅K)?

Answer:

a

    [tex]c = \frac{m_2 * c_w (T - T_2)}{m_1 * (T_1 - T) }[/tex]

b

  [tex]c = 2587.14 \ J /(kg \cdot K)[/tex]

Explanation:

From the question we are told that

    The mass of the material is  [tex]m_1 = 0.41 \ kg[/tex]

     The temperature is  [tex]T_1 = 86 ^oC[/tex]

      The mass of water is  [tex]m_2 = 1.7 \ kg[/tex]

      The temperature of water is  [tex]T_2 = 22^oC[/tex]

      The specific heat of water is  [tex]c_w = 4186 \ J/(kg\cdot K)[/tex]

       The temperature of the system is  [tex]T= 30 .3^o C[/tex]

Generally heat lost by the unknown material =  heat gained by water

Generally the heat gained by water is mathematically represented as  

        [tex]Q_2= m_2 * c_w (T - T_2)[/tex]

=>      [tex]Q_2= 1.7 * 4186 (30.3 - 22)[/tex]

=>      [tex]Q_2= 59064.46 \ J[/tex]

Generally the heat lost by the unknown material  is mathematically represented as        

        [tex]Q_1= m_1 * c* (T_1 - T)[/tex]

        [tex]m_2 * c_w (T - T_2) = m_1 * c* (T_1 - T)[/tex]

=>       [tex]c = \frac{m_2 * c_w (T - T_2)}{m_1 * (T_1 - T) }[/tex]

Here  c is the specific heat capacity of the unknown material

=>      [tex]Q_1= 0.41 * c (86 - 30.3)[/tex]

=>      [tex]Q_1= 22.83 c[/tex]        

So

           [tex]59064.46 = 22.83 c[/tex]

=>         [tex]c = \frac{59064.46 }{ 22.83}[/tex]

=>         [tex]c = 2587.14 \ J /(kg \cdot K)[/tex]

HELP ASAP!!!! WILL GIVE BRAINLIEST!

What are the functions of ribosomes, the endoplasmic reticulum, vesicles, and the Golgi apparatus?

Answers

The endoplasmic reticulum takes the proteins that are made by the ribosomes and folds them into sacs that are called cisternae. It then transports these folded proteins to the Golgi apparatus.

Ribosomes, endoplasmic reticulum, vesicles, and the Golgi apparatus are the organelles present in the eukaryotic cell. They are involved in various roles and functions involving proteins.

What are the functions of the organelles?

Ribosomes are the organelles involved in the transcription and translation process to synthesize proteins and transport them from ER to the vesicles. The endoplasmic reticulum (ER) is a membraneous structure that along with ribosomes is involved in lipid and protein synthesis.

The proteins synthesized from ER are transported to the Golgi body through the vesicles. They even eliminate the waste from the cell. The Golgi apparatus receives proteins from ER and then packs, modifies, and transports them to the target location.

Therefore, the ER, ribosomes, Golgi, and vesicles are involved in protein synthesis and transportation.

Learn more about cell organelles, here:

https://brainly.com/question/14798609

#SPJ2

two Force one of 12 Newton and another 24 Newton acts at 90 degree with each other find the resultant of two force and its direction

Answers

Answer:

Fr = 26.83 [N]

Explanation:

To solve this problem we must use the Pythagorean theorem, since the forces are vector quantities, that is, they have magnitude and density. Therefore the Pythagorean theorem is suitable for the solution of this problem.

[tex]F_{r}=\sqrt{(12)^{2}+(24)^{2} } \\F_{r}=26.83[N][/tex]

what is the correct answer?

Answers

Answer:

Option (4)

Explanation:

Given polynomial is,

P(x) = 1x³ - 7x² + 2x + 40

If (x - 5) is a factor of the given polynomial,

Synthetic division by x = 5,

5 |  1    -7     2     40

    ↓    5   -10   -40

     1    -2    -8      0

Therefore, factored form of the polynomial will be,

P(x) = (x - 5)(x²- 2x - 8)

Now we further factorize the expression (x² - 2x - 8),

(x² - 2x - 8) = x²- 4x + 2x - 8

                  = x(x - 4) + 2(x - 4)

                  = (x + 2)(x - 4)

Now fully factored form of the polynomial will be,

P(x) = (x - 5)(x + 2)(x - 4)

Therefore, remaining factors of the polynomial other than (x - 5) are (x - 4)(x + 2)

Option (4) will be the correct option.

a skier starts at rest at the top of a hill with 350 J of gravitational potential energy. Assuming energy is conserved, what is her final kinetic energy at the lowest point

Answers

Answer:

350Joules

Explanation:

According to law of Conservation of energy, the amount of energy at the used up at the start is equal to that at the end.

The initial energy used up is gravitational potential energy

Final energy at the lowest point is kinetic energy.

If the energy is conserved then it means energy is not used up during the process hence;

Initial Potential energy = Final kinetic energy

If the gravitational potential energy is 350Joules then her final kinetic energy at the lowest point will also be 350Joules

Two objects, one 4 times as massive as the other, are approaching each other under their mutual gravitational
attraction. When the separation between the objects is 100 km, the acceleration of the lighter object is 1 m/
s2. When the separation between them is 25 km, the acceleration of the heavier object is​

Answers

To Find :

The acceleration of the heavier object.

Solution :

Force of gravitation on lighter object by heavier object is :

[tex]F = \dfrac{Gm(4m)}{100^2}[/tex]

Acceleration of lighter object is given by :

[tex]a_s = \dfrac{4Gm}{100^2}\\\\m = \dfrac{50^2}{G}[/tex]          .....1)

Now, acceleration of heavier object when separation between them is 25 km :

[tex]4ma_h = \dfrac{Gm(4m)}{25}\\\\a_h = \dfrac{Gm}{25}[/tex].....2)

Putting value of m in equation 2, we get :

[tex]a_h = \dfrac{G\times 50^2}{G \times 25}\\\\a_h = \dfrac{2500}{25}\\\\a_h = 100\ m/s^2[/tex]

Therefore, the acceleration of the heavier object is​ 100 m/s².

A steel bridge is 5.5m long. If the linear expansivity of steel is 0.000011/℃, how much will it expand when temperature rise by 10 ℃? Give your answer in cm

Answers

Answer:

The expansion of the steel bridge is 0.0605 cm

Explanation:

The given length of the steel bridge, L = 5.5 m

The linear expansivity of the steel bridge, [tex]\alpha_ L[/tex] = 0.000011/°C

The rise (change) in the temperature, ΔT = 10°C

Let, ΔL, represent the expansion of the steel bridge

Given that the linear expansivity, [tex]\alpha_ L[/tex], of a material is the change in the length of a material per unit length of the material per unit change in the temperature, we have;

[tex]\alpha_ L[/tex] = ΔL/(L × ΔT)

∴ ΔL = [tex]\alpha_ L[/tex] × L × ΔT = 0.000011 /°C × 5.5 m × 10 °C = 0.000605 meters

ΔL = 0.000605 meters

The expansion of the steel bridge, ΔL = 0.000605 meters = 0.000605 m × 100 cm/m = 0.0605 cm

A 0.2 kg baseball is pitched with a velocity of 40 m/s and is then batted to the pitcher with a velocity of 60 m/s. What is the magnitude of change in the ball's momentum?

Answers

Answer:

The magnitude of change in the ball's momentum is 4 kgm/s

Explanation:

Given;

mass of the ball, m = 0.2 kg

initial velocity of the ball, u = 40 m/s

final velocity experienced by the ball, v = 60 m/s

Therefore, the change in momentum of the ball is given as final momentum minus initial mometum;

ΔP = mv - mu

ΔP = m(v-u)

ΔP = 0.2 (60 - 40)

ΔP = 4 kgm/s

Therefore, the magnitude of change in the ball's momentum is 4 kgm/s

The magnitude of the change in the momentum of the baseball is 4 kgm/s.

To solve the problem above we need to use the formula of change in momentum

Change in momentum: This can be defined as the product of the mass and the change in velocity of a body.

The formula of change in momentum is

M = m(v-u).................. Equation 1

Where M = change in momentum, m = mass of the baseball, v = final velocity of the baseball, u = initial velocity of the baseball.

From the question

Given:

m = 0.2 kg v = 60 m/s u = 40 m/s

Substitute these values into equation 1

         M = 0.2(60-40)          M = 0.2(20)          M = 4 kgm/s

Hence, The magnitude of the change in the momentum of the baseball is 4 kgm/s

Learn more about change in momentum here: https://brainly.com/question/11789105

A rocket is fired vertically upwards starting frkm rest. It accelerates at 30m/s for 4secs. At the end of 4secs it runs out of fuel but continues to rise. How long does it rise with reference to firing position?

Answers

Answer:

t = 16.5 s

Explanation:

First we apply first equation of motion to the accelerated motion of the rocket:

[tex]v_{f1} = v_{i1} + at_{1}[/tex]

where,

vf₁ = final speed of rocket during accelerated motion = ?

vi₁ = initial speed of rocket during accelerated motion  = 0 m/s

a = acceleration of rocket during accelerated motion = 30 m/s²

t₁ = time taken during accelerated motion = 4 s

Therefore,

[tex]v_{f} = 0\ m/s + (30\ m/s^2)(4\ s)\\\\v_{f} = 120\ m/s[/tex]

Now, we analyze the motion rocket when engine turns off. So, the rocket is now in free fall motion. Applying 1st equation of motion:

[tex]v_{f2} = v_{i2} + g t_{2}[/tex]

where,

vf₂ = final speed of rocket after engine is off = 0 m/s

vi₂ = initial speed of rocket after engine is off  = Vf₁ = 120 m/s

g = acceleration of rocket after engine is off = - 9.8  m/s² (negative sign for upward motion)

t₂ = time taken after engine is off = ?

Therefore,

[tex]0\ m/s = 120\ m/s + (- 9.8\ m/s^2)(t_{2})\\\\t_{2} = \frac{120\ m/s}{9.8\ m/s^2}\\\\t_{2} = 12.25\ s[/tex]

So, the time taken from the firing position till the stopping position is:

[tex]t = t_{1} + t_{2}\\\\t = 4 s + 12.5 s[/tex]

t = 16.5 s

say something random cuz i already answered my own question

Answers

Answer:

The experimental setup, with car 1 is at the top of a ramp and car 2 at the bottom of the ramp  is explained below in details.

Explanation:

The meter pole should be located at the opening location of car second at the bottom of the ramp so that it regulates the portion of car second that will finish up the most distant away from the bottom of the ramp.

So, I think now you got your answer which is absolutely correct and it will help you.

Answer:

hello my good friend

Explanation:

If 300j of energy is available for every 75c of charge what is the potential difference

Answers

Answer: 4V

Explanation:

If 300j of energy is available for every 75c of charge, the voltage will be calculated by dividing the available energy by the charge. This will be:

= 300 / 75

= 4v

Therefore, the potential Difference will be 4V.

PLZ HELP IM REALLY CONFUSED a boy is playing catch with his friend. He throws the ball straight up. When it leaves his hand, the ball (2kg) is traveling 10m/s. Whats the ball's kinetic energy just as it leaves the boy's hand? What is the potential energy of the ball when it reaches the highest point

Answers

Answer:

K.E = 100 J

Final P.E = 100 J

Explanation:

The kinetic energy of any object can be given by the following formula:

[tex]K.E = (\frac{1}{2})mv^{2}[/tex]

where,

K.E = Kinetic Energy

m = mass of ball = 2 kg

v = speed of ball

Initially, v = 10 m/s. Therefore, the initial K.E is given as:

[tex]K.E = (\frac{1}{2})(2\ kg)(10\ m/s)^{2}[/tex]

K.E = 100 J

Now, at the highest point the K.E of the ball becomes zero. because the ball stops for a moment at the highest point and its velocity becomes zero. So, from Law of Conservation of energy:

Initial K.E + Initial P.E = Final K.E + Final P.E

Initial P.E is also zero due to zero height initially.

K.E + 0 = 0 + Final P.E

Final P.E = 100 J

Le manque de sommeil peut réduire la production d'insuline par le pancréas. L'insuline est responsable de métaboliser le sucre dans le sang. De quel ordre peut être la réduction d'insuline?Lecteur immersif

Answers

Answer:

Very big.

Explanation:

Very big reduction occurs in insulin production when a person did not sleep in 24 hours. Due to lack of sleep, reduction occurs in the production of insulin by the pancreas. Insulin is a hormone that is responsible for metabolizing sugar in the blood and if insulin is not secreted by the pancreas in normal concentration so the person get diabetes disease due to increasing amount of glucose in the blood.

Please help me on this!!!

Answers

The answer will be b
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