Please help

Consider a monochromatic electromagnetic plane wave propagating in the x direction. At a particular point in space, the magnitud

weqwewe [10]

Answer:

a) S = 2.35 10³ J/m²2 ,

b)and the tape recorder must be in the positive Z-axis direction.

the answer is 5

c) the direction of the positive x axis

Explanation:

a) The Poynting vector or intensity of an electromagnetic wave is

S = 1 /μ₀ E x B

if we use that the fields are in phase

B = E / c

we substitute

S = E² /μ₀ c

let's calculate

s = 941 2 / (4π 10⁻⁷ 3 10⁸)

S = 2.35 10³ J/m²2

b) the two fields are perpendicular to each other and in the direction of propagation of the radiation

In this case, the electro field is in the y direction and the wave propagates in the ax direction, so the magnetic cap must be in the y-axis direction, and the tape recorder must be in the positive Z-axis direction.

the answer is 5

C) The poynting electrode has the direction of the electric field, by which or which should be in the direction of the positive x axis

4 0

3 years ago

For a freely falling object weighing 3 kg : A. what is the object's velocity 2 s after it's release. B. What is the kinetic ener

Fed [463]

A) 19.6 m/s (downward)

B) 576 J

C) 19.6 m

D) Velocity: not affected, kinetic energy: doubles, distance: not affected

Explanation:

A)

An object in free fall is acted upon one force only, which is the force of gravity.

Therefore, the motion of an object in free fall is a uniformly accelerated motion (constant acceleration). Therefore, we can find its velocity by applying the following suvat equation:

$v=u+at$

where:

v is the velocity at time t

u is the initial velocity

$a=g=9.8 m/s^2$ is the acceleration due to gravity

For the object in this problem, taking downward as positive direction, we have:

$u=0$ (the object starts from rest)

$a=9.8 m/s^2$

Therefore, the velocity after

t = 2 s

is:

$v=0+(9.8)(2)=19.6 m/s$ (downward)

B)

The kinetic energy of an object is the energy possessed by the object due to its motion.

It can be calculated using the equation:

$KE=\frac{1}{2}mv^2$

where

m is the mass of the object

v is the speed of the object

For the object in the problem, at t = 2 s, we have:

m = 3 kg (mass of the object)

v = 19.6 m/s (speed of the object)

Therefore, its kinetic energy is:

$KE=\frac{1}{2}(3)(19.6)^2=576 J$

C)

In order to find how far the object has fallen, we can use another suvat equation for uniformly accelerated motion:

$s=ut+\frac{1}{2}at^2$

where

s is the distance covered

u is the initial velocity

t is the time

a is the acceleration

For the object in free fall in this problem, we have:

u = 0 (it starts from rest)

$a=g=9.8 m/s^2$ (acceleration of gravity)

t = 2 s (time)

Therefore, the distance covered is

$s=0+\frac{1}{2}(9.8)(2)^2=19.6 m$

D)

Here the mass of the object has been doubled, so now it is

M = 6 kg

For part A) (final velocity of the object), we notice that the equation that we use to find the velocity does not depend at all on the mass of the object. This means that the value of the final velocity is not affected.

For part B) (kinetic energy), we notice that the kinetic energy depends on the mass, so in this case this value has changed.

The new kinetic energy is

$KE'=\frac{1}{2}Mv^2$

where

M = 6 kg is the new mass

v = 19.6 m/s is the speed

Substituting,

$KE'=\frac{1}{2}(6)(19.6)^2=1152 J$

And we see that this value is twice the value calculated in part A: so, the kinetic energy has doubled.

Finally, for part c) (distance covered), we see that its equation does not depend on the mass, therefore this value is not affected.

5 0

3 years ago

1. define feed

Hatshy [7]

Answer:

1.Animal feed is food given to domestic animals in the course of animal husbandry

2.) Roughages B) Concentrates C) Feed supplements and Feed additives

3. Feed grains

4.pliers, vacuum lifters, magnetic lifters, and stock positioners

Explanation:

1.Animal feed is food given to domestic animals in the course of animal husbandry

2.) Roughages B) Concentrates C) Feed supplements and Feed additives

3. Feed grains 

4.pliers, vacuum lifters, magnetic lifters, and stock positioners

7 0

3 years ago

A proton is released from rest inside a region of constant, uniform electric field E1 pointing due North. 32.3 seconds after it

NARA [144]

Answer:

E₂ / E₁ = 521.64 / 5.95 =87.67

Explanation:

Let d be the distance covered inside electric field . Lt q be the magnitude of charge.

Force under field E₁ = q E₁

acceleration = qE₁/ m

d = 1/2 a t²

d = .5 ( qE₁ / m) x 32.3²

d = 521.64 ( qE₁ / m)

Similarly for return journey,

d = .5 x ( qE₂ / m) x 3.45²

d = 5.95x( qE₂ / m)

521.64 ( qE₁ / m) = 5.95x( qE₂ / m)

E₂ / E₁ = 521.64 / 5.95 =87.67

8 0

3 years ago

Why all planetary objects have different amount of gravity?

Paladinen [302]

Answer:

Why do scientists usually talk about mass rather than weight? An object's weight is dependent on its mass and how strongly gravity pulls on it. The strength of gravity depends on how far away one object is from another. That's why the same object weighs different amounts on different planets.

Explanation: on Google

3 0

3 years ago