Which of the following statements is true?

What is the index of refraction of a material in which the speed of light is 7.50% slower than the speed of light in vacuum?

Inessa [10]

Answer:

The value is $n = 1.081$

Explanation:

From the question we are told that

The speed of in a vacuum is $c = 3.0 *10^{8} \ m/s$

The speed of light in the material is $v = c -0.075c = 0.925 c = 0.925 * 3.0*10^{8} = 2.775 *10^{8} \ m/s$

Generally the reflection of the material is mathematically represented as

$n = \frac{c}{v}$

=> $n = \frac{3.0*10^{8}}{2.775 *10^{8}}$

=> $n = 1.081$

8 0

3 years ago

Which of these results in kinetic energy of an object? position motion mass volume

Ray Of Light [21]

Answer:

motion

Explanation:

the motion causes static which is kinetic energy

3 0

3 years ago

Read 2 more answers

Windmills are used to convert wind energy into a more useful form. In most cases, there are three

sdas [7]

The kinetic energy of the wind ==> causes ==>
   the windmill to turn (mechanical energy) ==>
   which is used to turn an electric generator ==>
      which generates electrical energy.

4 0

3 years ago

Una tortuga recorre una pista de 1,25 km que tiempo emplearia si lleara una velocidad de 0,2 km/h

Marina86 [1]

Responder:

<h2>5 horas </h2>

Explicación:

La velocidad se define como el cambio de distancia de un cuerpo con respecto al tiempo. Matemáticamente, Velocidad = Distancia / Tiempo

Dada la velocidad del coche = 0,25 km / hy la distancia = 1,25 km

El tiempo se expresa a partir de la fórmula como Tiempo = Distancia / Velocidad

La sustitución de los valores dados en la fórmula dará;

Tiempo = 1,25 km / 0,25 km / h

Tiempo = 5 horas

Por lo tanto, la tortuga tardará 5 horas en viajar a una velocidad de 0,2 km / h.

7 0

3 years ago

A tiny object carrying a charge of +44 μC and a second tiny charged object are initially very far apart. If it takes 21 J of wor

STatiana [176]

Answer:

The magnitude of the second charge is $\rm 1.062\times 10^{-7}\ C$ or $\rm 0.1062\ \mu C.$

Explanation:

The work done in bringing a charged particle from one point to another in the presence of some electric field is equal to the change in the electric potential energy of the charge in moving from one point to another.

The electric potential energy of some charge $q_o$ at a point in the electric field of another charge $q$ is given by the product of the amount of charge $q_o$ and electric potential at that point due to the charge $q$ .

$U = q_o\ V.$

The electric potential at that point is given by

$V = \dfrac{kq}{r}.$

where $k$ is the Coulomb's constant.

Therefore,

$U=q_o\ \dfrac{kq}{r}.$

Now, We have given two charges $q_1 = +44\ \mu C = +44\times 10^{-6}\ C$ and $q_2$ , whose value is to be found.

When the two charges are infinitely dar apart, the electric potential energy of the system is given by

$U_i = \dfrac{kq_1q_2}{\infty}=0.$

When the coordinates of position of the two charges are

$(x_1,\ y_1) = (1.00\ mm,\ 1.00\ mm).\\(x_2,\ y_2) = (1.00\ mm,\ 3.00\ mm).$

The distance between the two charges is given by

$r=\sqrt{(x_2-x_1)^2+(y_2-y_1)^2}=\sqrt{(1.00-1.00)^2+(3.00-1.00)^2}=2.00\ mm = 2.00\times 10^{-3}\ m.$

The electric potential energy of the charges in this configuration is given by

$U_f = \dfrac{kq_1q_2}{r}\\=\dfrac{(8.99\times 10^9)\times (+44\times 10^{-6})\times q_2}{2.00\times 10^{-3}}\\=1.9778\times 10^8\times q_2.$

The change in the electric potential energy of the system is equal to the work done to bring the system from inifinitely far apart position to given configuration.

Therefore,

$W = U_f-U_i\\21=(1.9778\times 10^8\times q_2)-0\\\Rightarrow q_2 = \dfrac{21}{1.9778\times 10^8}\\=1.062\times 10^{-7}\ C\\=0.1062\times 10^{-6}\ C\\=0.1062\ \mu C.$

6 0

3 years ago