Uma bola é lançada para cima com a velocidade inicial de 20m/s. A sua aceleração é constante e igual a 10m/s² para baixo. Quanto tempo permanece a bola no ar? Qual é a maior altura atingida pela bola? Quando a bola está a 15 m de altura em relação ao solo?

Explanation:

Khi một hạt thực hiện SHM Đang chuyển động từ vị trí cực biên về vị trí trung bình, thì vận tốc và gia tốc cùng hướng, tức là hướng về vị trí trung bình

Answer:

Consequently the statement is FALSE

Explanation:

The process of emission of electrons or photoelectric effect, was explained by Einstein, assuming that light behaves as formed by how many so-called photons and each one of them collides with an electron, therefore to start an electron the incident photon energy must be greater than the work function of the material.

            E =K + Ф

By mentioning the intensity we increase the number of photons but we do not increase their energy.

Consequently the statement is FALSE

Answer:

1.17

Explanation:

Given that,

The refractive index of ice wrt air = 1.31

The refractive index of rock salt wrt air = 1.54

We need to find the refractive index of rock salt with respect to ice.

We know that,

refractive index = (speed of light in air or vaccum)/( speed of light in that medium)

So,

The speed of light in ice = c/(1.31)

The speed of light in rock salt = c/(1.54)

So, the refractive index of rock salt with respect to ice​ is :

[tex]\mu=\dfrac{1.54}{1.31}\\\\=1.17[/tex]

So, the required refractive index of rock salt wrt ice is 1.17.

Answer:

The net calorific value of the fuel 1 is 40000 kilojoules per kilogram.

The net calorific value of the fuel 2 is 50000 kilojoules per kilogram.

Explanation:

The net calorific value is equal to the heat produced ([tex]Q[/tex]), in kilojoules, divided by the mass of the burnt fuel ([tex]m[/tex]). We proceed to calculate the net calorific value of each fuel:

Fuel 1 ([tex]m = 4\,kg[/tex], [tex]Q = 160000\,kJ[/tex])

[tex]L = \frac{160000\,kJ}{4\,kg}[/tex]

[tex]L = 40000\,\frac{kJ}{kg}[/tex]

The net calorific value of the fuel 1 is 40000 kilojoules per kilogram.

Fuel 2 ([tex]m = 2\,kg[/tex], [tex]Q = 100000\,kJ[/tex])

[tex]L = \frac{100000\,kJ}{2\,kg}[/tex]

[tex]L = 50000\,\frac{kJ}{kg}[/tex]

The net calorific value of the fuel 2 is 50000 kilojoules per kilogram.

Answer:

ya bestie Anda benar terima kasih nanti sekarang selamat tinggal

Answer:

  (D)  4

Explanation:

The percentage error in each of the contributors to the calculation is 1%. The maximum error in the calculation is approximately the sum of the errors of each contributor, multiplied by the number of times it is a factor in the calculation.

  density = mass/volume

  density = mass/(π(radius^2)(length))

So, mass and length are each a factor once, and radius is a factor twice. Then the total percentage error is approximately 1% +1% +2×1% = 4%.

_____

If you look at the maximum and minimum density, you find they are ...

  {0.0611718, 0.0662668} g/(mm²·cm)

The ratio of the maximum value to the mean of these values is about 1.03998. So, the maximum is 3.998% higher than the "nominal" density.

The error is about 4%.

_____

Additional comment

If you work through the details of the math, you will see that the above-described sum of error percentages is just an approximation. If you need a more exact error estimate, it is best to work with the ranges of the numbers involved, and/or their distributions.

Using numbers with uniformly distributed errors will give different results than with normally distributed errors. When such distributions are involved, you need to carefully define what you mean by a maximum error. (By definition, normal distributions extend to infinity in both directions.) While the central limit theorem tends to apply, the actual shape of the error distribution may not be precisely normal.

Answer:

Explanation:

#CARRYONLEARNING

justoko2

Answer:

The ratio of the escape velocity to the orbital velocity is [tex]\sqrt 2[/tex].

Explanation:

The minimum velocity given to an object so that it escapes from the earth's gravitational pull is called escape velocity.

The formula of the escape velocity is

[tex]v=\sqrt\frac{2GM}{R}[/tex]

The velocity of an object in the orbit around the earth is called orbital velocity.

The formula of the orbital velocity is

[tex]v=\sqrt\frac{GM}{R}[/tex]

The ratio of the escape velocity to the orbital velocity is

[tex]\frac{v_e}{v_o}=\sqrt 2[/tex]

Answer:Whenever the velocity of the object increases or usually doubles, the kinetic energy will be quadrupled. If in case you are not familiar with kinetic energy, this is known as the type of energy that is in motion. The greater the mass of the object, the greater the total of the energy

Explanation:

Change to an object would quadruple its kinetic energy Increasing its velocity to twice its original value

In physics, the kinetic energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes. The same amount of work is done by the body when decelerating from its current speed to a state of rest. Formally, kinetic energy is any term in a system's Lagrangian which includes a derivative concerning time.

In classical mechanics, the kinetic energy of a non-rotating object of mass m traveling at a speed v is [tex]{\textstyle {\frac {1}{2}}mv^{2}}[/tex]

In relativistic mechanics, this is a good approximation only when v is much less than the speed of light.

The standard unit of kinetic energy is the joule, while the English unit of kinetic energy is the foot-pound.

Learn more about kinetic energy

https://brainly.com/question/12337396

#SPJ2

Answer:

The Reactants                                                       Products                          

Copper sulfate + zinc             →                        Zinc sulfate + copper

aluminum + copper chloride     →                    Aluminum chloride + Copper

Copper + Oxygen                     →                      Copper oxide

Explanation:

The Reactants                                                       Products                          

Copper sulfate + zinc                                        Zinc sulfate + copper

aluminum + copper chloride                            Aluminum chloride + Copper

Copper + Oxygen                                             Copper oxide

First reaction can be described as a single replacement reaction

Second reaction is also a single replacement reaction just like the first reaction

The third is a synthesis reaction ( i.e. reaction in which elements combine to form single compound )

Answer:

an o point i think

Explanation:

Answer:

Measurement is the quantification of attributes of an object or event, which can be used to compare with other objects or events

Answer:

The comparison of an unknown quantity with a known quantity is called measurement

Answer:

Explanation:

I'm assuming you missed the decimal point in the initial velocity and that it should be 4.0 m/s. If after a half of a second it is moving a tiny bit slower, it would be because of air resistance. You can only neglect air resistance if the problems you are doing tell you neglect it.

Answer:

Air resistance

Explanation:

I got it correct on the quiz :)

1. set up the equation

2. multiply the variables

3. analyze your results

Answer:

Q=21600C

Explanation:

Q=It.

Data

I=12A

t=30min

convert time from minutes to second

t=60*30

=1800s

Q=?

Q=It

=(12A)*(1800s)

Q=21600C

Explanation:

First find the area of the entire floor:

Area of a rectangle= length × width

( 4000mm× 3600mm)

14400000mm²

Area of one square tile??= side ×side

12cm×12cm

144cm²

Convert cm to mm

1cm²=100mm²

144cm²=144cm²/1cm²×100mm²

=14,400mm²

Number of tiles required to cover the entire floor= 14400000mm²/14400mm²

=1000

Answer:

1.76km

Explanation:

Here,

1mi = 1.6km

1.10 miles = 1.6 x 1.10 km

= 1.76 km

Answer:

A. Mg+2

Explanation:

im not sure, but since it lost two electrons which have a negative charge it gained two charge.

Answer:

v = 4 m/s

Explanation:

Given :

Ball X :

Mass, m1 = 8kg ;

Initial Velocity, u1 = 2 m/s

Final velocity, v1 = 0

Ball Y:

Mass, m2 = 4kg ;

Initial Velocity, u2 = 0 m/s

Final velocity, v2 = v

(m1u1 + m2u2) = (m2v2 + m1v1)

(8*2 + 4*0) = (4*v + 4*0)

16 + 0 = 4v + 0

16 = 4v

v = 16 / 4

v = 4 m/s

Answer:

Explanation:

This is the Law of Momentum Conservation which for us looks like this:

[tex][m_xv_x+m_yv_y]_b=[m_xv_x+m_yv_y]_a[/tex] and that should look familiar to you if this is what you are doing in physics. Filling in our particular info:

[(8.0 × 2.0)+ (4.0 × 0.0)] = [(8.0 × 0.0) + (4.0v)] and

16 + 0 = 0 + 4.0v and

16 = 4.0v so

v = 4.0 in the direction of ball X

Answer:

Explanation:

These Hooke's Law problems are tricky. Here's what we need to know that clears up the problem entirely. The final and also the max speed of the block will be reached at the point where the potential energy of the system is 0. So the equation we need, namely,

[tex]KE+PE=\frac{1}{2}kA^2[/tex] can be simplified down to

[tex]KE=\frac{1}{2}kA^2[/tex] and we solve this first for KE:

[tex]KE=\frac{1}{2}(85)(.30)^2[/tex] and, paying NO attention whatsoever to significant digits here (because if you did the answer you get is not one of the choices)

KE = 3.825 J.  Now we can use that value of kinetic energy and solve for the speed we need:

[tex]KE=\frac{1}{2}mv^2[/tex] so

[tex]3.825=\frac{1}{2}(.50)v^2[/tex] so

[tex]v=\sqrt{\frac{2(3.825)}{.50} }[/tex] so

v = 3.91 m/s

Melting: the substance changes back from the solid to the liquid

Evaporation: the process by which water changed from a liquid to a gas.

Boiling: the process by which a liquid turns into a vapor when it is heated to it's boiling point.

Condensation: the substance changed from a gas to a liquid

Freezing: the substance changed from a liquid to solid.

Answer:

Melting is a process that causes a substance to change from a solid to a liquid.

Evaporation is the process of turning from liquid into vapour.

Boiling is the rapid vaporization of a liquid, which occurs when a liquid is heated to its boiling point, the

Condensation is the process of water vapor turning back into liquid water

Freezing is a phase transition where a liquid turns into a solid when its temperature is lowered below its freezing point

Answer:

[tex]F=0N[/tex]

Explanation:

From the question we are told that:

Charge [tex]Q=4.88 x 10-6 C[/tex]

Velocity [tex]v= 265m/s[/tex]

Angle [tex]\theta =0 \textdegree[/tex]

Magnetic field [tex]B=0.0579T[/tex]

Generally the equation for Force is mathematically given by

 [tex]F=Q(\=v*\=B)[/tex]

 [tex]F=qvBsin\theta[/tex]

Therefore

 [tex]F=qvBsin0 \textdegree[/tex]

 [tex]F=0N[/tex]

Answer:

0 newtons

Explanation:

When a moving charge is parallel to the magnetic field, it feels no Magnetic force at all.

Even if the Magnetic Field is 100,000,000 Tesla!

Answer:

Refer to the attachment!~

it occur kinetic energy

when breaking in a hybrid

vehicle.

hope it helps

Answer:

it occur kinetic energy when breaking in a hybrid

vehicle .

hope it is helpful to you ☺️

Answer:

h2 PRD algo trata gevbjjgcvnkoytewxc.

Answer:

12.5kg

Explanation:

The process is explained in the paper

Answer:

The pressure on piston 1 is always equal to the pressure on piston 2. ... It is equal to the force on piston 1, multiplied by A2/A1. Hydraulic systems are called force multipliers for exactly this reason. A small force can be increased by using hydraulics

Explanation:

Radhe Radhe❤

Answer:

Netball is a ball sport for two teams of seven players it's rules are published in print and online by the international netball federation Games are played on a rectangular court divided into thirds with a raised goal at coach short end

Explanation:

It will help you

Answer:

hlw its jess bregoli

your answer is here

SI (International System of Units) (meter-kilogram-second-ampere-kelvin-mole-candela)

FPS (foot-pound-second)

MKS (meter-kilogram-second)

CGS (centimeter-gram-second)

EMU (Electromagnetic) (centimeter-gram-second-abampere)

ESU (Electrostatic) (centimeter-gram-second-abcoulomb)

Atomic (bohr-electron mass-atomic second-electron)

MTS (meter-tonne-second)

Explanation:

hope it may help you !!

Answer:

there are 4 types of systems. They are ,

SI - accepted world wide

MKS - meter  kilogram  second

CGS - centimeter  gram  second

FPS - foot  pound  second

hope it helps.

Answer:

22

Explanation:

Answer:

45.5 v

Explanation:

I = 1.3 A

R = 35 Ω

V = I * R

V = 1.3 * 35 = 45.5 v