Confused about this question. Can someone help? :)

Answer:

The combined velocity is 8.61 m/s.

Explanation:

Given that,

The mass of a truck, m = 2800 kg

Initial speed of truck, u = 12 m/s

The mass of a car, m' = 1100 kg

Initial speed of the car, u' = 0

We need to find the combined velocity the moment they stick together. Let it is V. Using the conservation of momentum.

[tex]m_1v_1+m_2v_2=(m_1+m_2)V\\\\V=\dfrac{m_1v_1+m_2v_2}{(m_1+m_2)}\\\\V=\dfrac{2800\times 12+0}{2800+1100}\\\\V=8.61\ m/s[/tex]

So, the combined velocity is 8.61 m/s.

Answer:

D. As the optical density increases, the refractive index increases

Answer: the answer is D

Explanation: I took the test

Answer:

False

Explanation:

The range of a projectile is the horizontal height reached

Answer:

a. 90 dB

b. 80 dB

Explanation:

The given parameter of the sound is as follows;

The level to which the headphones are tuned = All the way up

The intensity of the sound of the headphones when tuned all the way up = 100 dB

a. The relationship between level change in loudness, ΔL, and the ratio of loudness, 'x', is presented as follows;

ΔL = 10·log₂(x) ≈ 33.22·log(x)

Therefore, for a sound to be half as loud, we have x = 1/2, therefore;

ΔL = 10·log₂(1/2) = 10·log₂(2⁻¹) = -10 ≈ 33.22·log(1/2)

The change in the intensity level for a sound half as loud, ΔL = -10 dB

Given that the sound was initially at 100 dB, the new level for a sound half as loud = 100 dB + ΔL = 100 dB - 10 dB = 90 dB

The decibel level the music must be set for a sound half as loud = 90 dB

b. In order for the sound to be 1/4 as loud, we have;

ΔL = 10·log₂(1/4) = 10·log₂(2⁻²) = -20

Therefore, the change in the level of the sound intensity level, ΔL by -20 dB will given a sound that is 1/4 as loud

The initial intensity level = 100 dB

The intensity level for a sound 1/4 as loud = 100 dB - 20 dB = 80 dB

Explanation:

Given:

m1 = 0.55 kg

m2 = 0.45 kg

vi1 = +5.8 m/a

vi2 = -3.9 m/a

Solve for V

m1vi1 + m2vi2 = (m1 + m2)V

(0.55 kg)(+5.8 m/s) + (0.45 kg)(-3.9 m/s) = (0.55 + 0.45)V

V = +1.46 m/a

This means that the combined mass after the collision is moving to the right at 1.46 m/s

Answer:

A

Explanation:

Explanation:

work done is equals to force into displacement in the direction of force

Ans: D

Answer:

It is important because it furnishes information about the composition, the temperature and maybe the mass or relative velocity of the body that emits or absorbs it.

Explanation:

Answer:

Initial velocity is defined as the velocity at time t=0.

Its Unit is m/s.

represented by u.

calculated by using formula.

v=u+at

u=v-at.

Answer:

Initial velocity is the velocity which the body has in the beginning of the given time period

Hope it helps

-------☆ﾟ.･｡ﾟᵴɒƙυᴚᴀ_ƨȶäᴎ❀

Answer:

8.85

Explanation:

The computation of the charge that must place on them in order to create 1000 N/C field between the plates is shown below:

We know that

E = (Q/A) ÷ E_o

1000 = Q ÷ 0.01×8.85× 10^-12

Q = 8.85 × 10^-12

So,

The answer is 8.85

The above formula should be applied so that the correct value could come

And, the same would be relevant

Answer:

8.85

Explanation:

acellus

Answer:

Velocidad = 2 m/s

Explanation:

Dados los siguientes datos;

Distancia = 80 m

Tiempo = 40 s

Para encontrar la velocidad del automóvil;

La velocidad se puede definir como la tasa de cambio en el desplazamiento (distancia) con el tiempo.

La velocidad es una cantidad vectorial y, como tal, tiene magnitud y dirección.

Matemáticamente, la velocidad viene dada por la ecuación;

[tex] Velocidad = \frac {distancia} {tiempo} [/tex]

Sustituyendo en la fórmula, tenemos;

Velocidad = 80/40

Velocidad = 2 m/s

Answer:

Gamma rays and x rays

Explanation: just took the test

Gamma rays and X-rays have higher frequencies than the waves that make up ultraviolet light. Hence option D is correct.

Electromagnetic spectrum is nothing but the range of wavelengths or frequencies on which electromagnetic radiation extend. it is whole distribution of electromagnetic waves according to frequency or wavelength. Electromagnetic wave is nothing but a photon which carries energy. Photon wave has frequency, wavelength as well as amplitude.

Electromagnetic spectrum is show in figure.

There is inverse relation between wavelength and frequency as υ = c/λ

where υ is the frequency, λ is the wavelength and c is the speed of light.

as wavelength increases, frequency decreases vice verse.

In this figure we can see that radio waves has highest wavelength hence it has lowest frequency. X ray and gamma rays has lowest wavelength hence it has highest frequency.

Hence option D is correct.

To know more about electromagnetic waves, click :

https://brainly.com/question/18165320

#SPJ7.

Answer:

[tex]n=1.86*10^{-30}m^3[/tex]

Explanation:

From the question we are told that:

Fermi energy of conduction electrons [tex]E_f=0.548J[/tex]

Generally the equation for Fermi energy is mathematically given by

 [tex]E_f=\frac{3}{\pi}^2/3*\frac{h^2}{8m}*{n^{2/3}}[/tex]

 [tex]E_f=\frac{3}{\pi}^2/3*\frac{h^2}{8m}*{n^{2/3}}[/tex]

 [tex]{n^{2/3}}=\frac{E_f}{\frac{3}{\pi}^2/3*\frac{h^2}{8m}}[/tex]

Where

h= Planck's constant

 [tex]{n^{2/3}}=\frac{E_f}{\frac{3}{\pi}^2/3*\frac{h^2}{8m}}[/tex]

 [tex]{n^{2/3}}=\frac{0.548J}{3.62*10^{-19}}[/tex]

 [tex]n=(1.51*10^{-20})^{3/2}[/tex]

 [tex]n=1.86*10^{-30}m^3[/tex]

Answer:

Could you give information about the lab

Explanation:

Answer:

The spectrum of each astronomical object

Explanation:

I took the test and got it right

Answer:

A.

Explanation:

I did the test :D

Answer:

Nuclear reactors are the heart of a nuclear power plant. They contain and control nuclear chain reactions that produce heat through a physical process called fission. That heat is used to make steam that spins a turbine to create electricity.

Answer:

A nuclear power plant's heart is made up of nuclear reactors. They contain and regulate nuclear chain reactions, which produce heat via a physical process known as fission. This heat is converted to steam, which powers a turbine to generate energy.

Answer:

the answer is C a material or substance

Explanation:

BRAINLIEST PLZZZZZZZZZZZZZZZ

Answer:

the use of physics in our life is to be a science student.

Answer:

15 J

Explanation:

Work = Force x Distance

15= 30 x 0.5

Have a blessed day!

Answer:Pravat did 15 J of work

Explanation:

Answer:

using a seismograph

Explanation:

Answer:

An object's weight depends on its mass (the amount of matter it consists of) and the strength of the gravitational pull.

Answer:

A prism causes the different wavelengths of light or colors that can be found in white light because the prism is white, and white light contains all colors in the visible light spectrum. So an object that reflects all the colors in the visible light spectrum will appear white in color because white light contains all colors in the visible light spectrum.

Explanation:

I hope this helps! I just did a test with this question and I got the answer right! This is the answer that I put. Good luck :)

Answer:

2 = C

3 = B

1 = A

Explanation:

Answer:

Explanation:

its reading the caliper

as the 0 lines up w the 1/8" mark, it is 1 1/8"

Answer:

The minimum thickness will be stamped somewhere. You see there's part numbers and other things here you might need to use a wire brush to kind of clean it up but that's the thicknessUse a micrometer at the thinnest point on the surface of the rotor where it meets the pads to measure the minimum operational thickness. If your rotor needs to be cut or has worn passed this thickness, you'll need new rotors. You may also discover your rotor has Disc Thickness Variation.

Answer:

P = 12000 W

Explanation:

General data:

Work is force times unit of distance. So in order to calculate the power we must first calculate the work.

Formula:

Replace and solve

once the work is found, we proceed to find the power according to the formula:

The power of the crane is 12000 Watts.

Greetings.