help please....................​

Answer:

acceleration

Explanation:

it is the time rate change in velocity

Answer:

acceleration

Explanation:

Answer:

Input work is the work done on a machine as the input force acts through the input distance. This is in contrast to output work which is a force that is applied by the body or system to something else. Output work is the work done by a machine as the output force acts through the output distance.Jan 15, 2020 whhdbd dhd dvd s bs sbs shs shs sh s

Explanation:

avsvsyxsgzvs zvx shs dhx xbx dhd dvd dj

Physical changes are not represented by equations because it does not involve rearrangement of atoms.

Therefore, physical changes are not represented by equations because it does not involve rearrangement of atoms.

Learn more about physical change at: https://brainly.com/question/864557

Answer:

13.78 m/s

Explanation:

Given that:

The mass of the girl & her bicycle = 42 kg

The speed at the top of the hilll= 4 m/s

The height of the hill = 14.3 m

The length of the hill (distance) = 112 m

The frictional force = 20 N

To find the speed at the bottom of the hill; we need to carry out the following processes.

The workdone by gravity = mass × acceleration due to  gravity × Δh

= 42 × 9.8 × ( 14.3 - 0 )

= 5885.88 joules

The workdone by the friction = Force × distance = - 20 × 112    (since she is riding down the hill)

The workdone by the friction = -2240 Joules

The initial Kinetic friction = 1/2 mv²

= 1/2 × 42 × 4²

= 336 Joules

The final kinetic energy = Initial Kinetic energy + total work  

The final kinetic energy = (336 + 5885.88 - 2240) Joules

The final kinetic energy = 3981.88   Joules

Using the final kinetic energy =   1/2 mv²

3981.88  = 1/2 × 42 × v²

3981.88  = 21 v²

v² = 3981.88/21

v² =189.61

v = [tex]\sqrt{189.61}[/tex]

v = 13.78 m/s

Therefore, the speed at the bottom = 13.78 m/s

Answer:

B. You would weigh the same on both planets because their masses and the distance to their centers of gravity are the same.

Explanation:

Given that Planets A and B have the same size, mass.

Let the masses of the planets A and B are [tex]m_A[/tex] and [tex]m_B[/tex] respectively.

As masses are equal, so [tex]m_A=m_B\cdots(i)[/tex].

Similarly, let the radii of the planets A and B are [tex]r_A[/tex] and [tex]r_B[/tex] respectively.

As radii are equal, so [tex]r_A=r_B\cdots(ii)[/tex].

Let my mass is m.

As the weight of any object on the planet is equal to the gravitational force exerted by the planet on the object.

So, my weight on planet A, [tex]w_A= \frac {Gm_Am}{r_A^2}[/tex]

my weight of planet B, [tex]w_B=\frac {Gm_Bm}{r_B^2}[/tex]

By using equations (i) and (ii),

[tex]w_B=\frac {Gm_Am}{r_A^2}=w_A[/tex].

So, the weight on both planets is the same because their masses and the distance to their centers of gravity are the same.

Hence, option (B) is correct.

Answer:

Static Friction

It is the friction that exists between a stationary object and the surface on which it's resting.

Sliding friction

It is the resistance created by two objects sliding against each other.

Rolling friction:-

It is the force resisting the motion when a body rolls on a surface.

Answer:

The answer is C- the atoms have different. A. Topic numbers

Explanation:

if they have the same neutrons and protons but not electrons the atomic numbers cant be the same if they dont have all 3 of the same numbers.

(on edge 2020-2021)

The atoms have different atomic numbers.

The atomic number of an atom is equal to the number of protons in its nucleus. Since Atom A and Atom B have the same number of protons and neutrons, they have the same atomic mass, which is the sum of protons and neutrons in the nucleus.

However, the number of electrons in an atom can vary. An atom is electrically neutral, which means it has the same number of protons and electrons. If Atom A and Atom B have different numbers of electrons, they will have different charges. One atom may have gained or lost electrons, making it either negatively charged (anion) or positively charged (cation), while the other remains neutral.

The chemical symbol of an element represents the identity of the element, and it is determined by the number of protons in the nucleus, which is the atomic number. Since the atoms have different atomic numbers, they will have different chemical symbols.

Therefore, the correct statement is that the atoms have different atomic numbers, as their atomic numbers determine their chemical identity.

To learn more about neutrons, here

https://brainly.com/question/31977312

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Answer:

because metals a good conductor of electricity.

Explanation:

Metal particles are held together by strong metallic bonds, which is why they have high melting and boiling points. The free electrons in metals can move through the metal, allowing metals to conduct electricity.

Explanation:

Metals are good conductors of electricity and are ducitile i.e. can be drawn into thin wires hence they are used for making wires.

Given :

The focal length of a concave mirror is 18 cm.

To Find :

The radius of curvature of the concave mirror.

Solution :

We know,

[tex]\text{Focal length}=\dfrac{\text{Radius of curvature}}{2}\\\\F=\dfrac{R}{2}\\\\R = 18\times 2\ cm\\\\R = 36 \ cm[/tex]

Therefore, the radius of curvature of concave mirror is 36 cm.

Hence, this is the required solution.

Answer:

Option (B) is correct.

Explanation:

Given that the molecules of hydrogen gas ([tex]H_2[/tex]) react with molecules of oxygen gas ([tex]O_2[/tex]) in a sealed reaction chamber to produce water ([tex]H_2O[/tex]).

The governing equation for the reaction is

[tex]2H_2 +O_2 \rightarrow 2H_2O[/tex]

From the given, the only fact that can be observed that 2 moles of [tex]H_2[/tex] and 1 mole of [tex]O_2[/tex] reacts to produce 2 moles of [tex]H_2O[/tex].

As the mass of 1 mole of [tex]H_2 = 2[/tex] grams ... (i)

The mass of 1 mole of [tex]O_2 = 32[/tex] grams ...(ii)

The mass of 1 mole of [tex]H_2O = 18[/tex] grams (iii)

Now, the mass of the reactant = Mass of 2 moles of [tex]H_2[/tex] + mass 1 mole of  [tex]O_2[/tex]

[tex]= 2 \times 2 + 32[/tex]  [ using equations (i) and (ii)]

[tex]=4+32 = 36[/tex] grams.

Mass of the product = Mass of 2 moles of [tex]H_2O[/tex]

[tex]=2\times 18[/tex] [ using equations (iii)]

=36 grams

As the mass of reactants = mass of the product.

So, mass is conserved.

Hence, option (B) is correct.

Answ40x-50 =2334

Explanation:

idk

Answer:

Terrorists:scary,ruthless,morbid. Pretty:beautiful,sweet. Gay:happy,sweet,nice

Explanation:

Reeee

Answer:

Alternating

Explanation:

It is alternating because it is easy to distribute long distance.

Direct current is found in batteries and have large voltage drop over distance.

Answer:

alternating

Explanation:

it was right on my quiz

Answer:

What are the opinions?

Explanation:

We need to see a question and opinion

Answer:

Reason for the difference in the ranges of the ball and the cart:

"the average speed of the cart is less than the instant speed of the cart at the time of throwing the ball".

Explanation:

Assuming that the air friction is negligible.

Given that the ball lands on the ground a little before the cart.

So, the range of the ball is more than the range of the cart in the same time interval.

Let the instant speed of the cart is v m/s  at the time of throwing the ball in the vertically upward direction, so the speed of the ball in the horizontal direction = v m/s.

Let t be the total time of flight of the ball.

As the gravitational force is acting in the downward direction so it will not change the horizontal velocity of the ball.

So, the range covered by the ball [tex]= vt[/tex] m.

Let u be the average speed of the cart for the time t s (same as the time of flight of ball).

So, the distance by the cart [tex]= ut[/tex] m

As the range of the ball is more than the range of the cart in the same time interval, so

[tex]vt > ut \\\\\Rightarrow v>u.[/tex]

So, the reason for the difference in the ranges of the ball and the cart is "the average speed of the cart is less than the instant speed of the cart at the time of throwing the ball".

Answer:

15/30 = .5 miles/m

Explanation:

v = d/t

velocity = 15 / 30

Answer:

Explanation:

The mass of the object can be found by using the formula

[tex]m = \frac{f}{a} \\ [/tex]

f is the force

a is the acceleration

From the question we have

[tex]m = \frac{20}{5} \\ [/tex]

We have the final answer as

Hope this helps you

Answer:

XD

Explanation:

XD furry friend

Furry's muck eachother

Answer:

1. What is not considered a cardiovascular workout?

A. Jogging

B. Sit ups

C. Jump Ropes

D. Burpees

Explanation:

I am sorry, I am in middle school and I only have one question.

Answer: use the step down transformers to reduce these voltages in the power lines before they are supplied to the users.

Explanation:

Answer:

It passes through a step-down transformer.

Explanation:

Electric current in power lines must be stepped down before they enter our homes because they carry a very high voltage.

The voltage can destroy appliances that have very low voltage.

Answer

4

Explanation:

four rays can also explain the ray diagram if the object is at infinity

Answer: Is that a question?

Explanation:

Answer:

a

Explanation:

using f=ma

a=f/m

=18.9/0.145

=130.344

=130

Answer:

Atoms

Explanation:

An atom is the smallest particle of an element that still has the properties of that element

Answer:

[tex] \huge{ \boxed{ \bold{ \sf{Atom}}}}[/tex]

✎ Let's explore about Atoms :

⟶ The smallest particle of an element which takes part in a chemical reaction without its division is called an atom. All the atoms of an element are the same. The atoms of different elements are different. All the atoms of iron in an iron nail are the same. But the atoms of iron are different from the atoms of copper. All the atoms of elements except hydrogen are made up of electron , proton and neutron. A hydrogen atom is made up of only electron and proton. Most of the atoms of elements do not exit independently except the atoms of inert gases like helium , neon , krypton etc.

____________

✑ EXTRA INFO :

STRUCTURE OF THE ATOM :

⟶ According to scientists , an atom is a sphere with a diameter of approximately [tex] \sf{ {10}^{ - 10}} [/tex] m. In the [tex] \sf{ {19}^{th} }[/tex] century , it was found that there are other smaller particles in an atom. These smaller particles are called subatomic or elementary or fundamental particles. The main subatomic particles are electrons , protons and neutrons. Among three subatomic particles of an atom , protons and neutrons are located at the centre of the atom called nucleus. The nucleus shows the positive charge due to the positive charge of protons. It also helps to find atomic weights . Electrons are revolving around the nucleus in their respective orbits or shells. The number of electrons present in an atom determines the size of the atom as it occupies more space as compared to the nucleus. In any atom , the number of negatively charged electrons in the orbits is equal to the number of positively charged protons in the nucleus. So, An atom is electrically neutral.

Hope I helped!

Have a wonderful day ! ツ

~TheAnimeGirl ♡

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