can an electric field exist in a vacuum?

Answers

Answer 1
NO it can’t because that’s illegal and that’s such a hate crime so no it can’t exist in a vaccuum

Related Questions

Consider a solenoid of length L, N windings, and radius b (L is much longer than b). A current I is flowing through the wire. If the length of the solenoid became twice as long (2L), and all other quantities remained the same, the magnetic field inside the solenoid would Consider a solenoid of length , windings, and radius ( is much longer than ). A current is flowing through the wire. If the length of the solenoid became twice as long (2), and all other quantities remained the same, the magnetic field inside the solenoid would:_______.
a. stay the same.
b. become twice as strong as initially.
c. become half as strong as initially.

Answers

Answer:

The magnetic field inside the solenoid would be 1/2

Explanation:

The magnitude of the magnetic field (B) inside a solenoid is given by equation –  

B=μonIB=μonI

Where

I is the current  

n is the number of turn per unit  

n = N/L , where N is the number of turns(windings) and L is the length of the solenoid.

μoμo is the permeability constant

So the formula becomes

B=μo(N)IB/L

If L is doubled, magnetic flux becomes half the original value

‏Explain how an electron emitted by the photoelectric effect can have kinetic energy less than threshold energy ?

Answers

Answer:

the photons (quanta of light) collide with the electrons, these electrons have to overcome the threshold energy that is the energy of union with the metal, and the energy that remains is converted to kinetic energy.

          K = E - Ф

Explanation:

The photoelectric effect is the emission of electrons from the surface of a metal.

This was correctly explained by Einstein, in his explanation the energy of the photons (quanta of light) collide with the electrons, these electrons have to overcome the threshold energy that is the energy of union with the metal, and the energy that remains is converted to kinetic energy.

          E = hf

          E = K + Ф

          K = E - Ф

The energy of the photons is given by the Planck relation E = hf and according to Einstein the number of joints must be added

            E = n hf

Therefore, depending on the value of this energy, the emitted electrons can have energy from zero onwards.

Liquid water is nearly 1,000 times denser than air. Thus, for every 32.0 feet (9.75 m) a scuba diver descends below the water's surface, the pressure increases by 1.00 atm. Human lungs have a volume of approximately 3.50 L. If a scuba diver descends to a depth of 80.0 feet where the pressure is 3.50 atm (2.50 atm from the water and 1.00 atm from the air pressure), then by how much does the volume of a 3.50 L surface sample of air decrease

Answers

Answer:

 ΔV = -2.1 L

Explanation:

To solve this exercise we can use the ideal gas equation for two points

         PV = nRT

          P₁V₁ = P₂ V₂

where point 1 is on the surface and point 2 is at the desired depth,

          V₂ = [tex]\frac{P_1}{P_2} \ V_1[/tex]

let's calculate

           V₂ = ( [tex]\frac{1 atm}{2.5 atm}[/tex] ) 3.5 L

            V₂ = 1.4 L

this is the new volume, the change in volume is

          ΔV = V₂ -V₁

          ΔV = 1.4-3.5

          ΔV = -2.1 L

An increase in the magnitude of which others quantities causes a reduction in centripetal force?
A. Mass
B.Radius of curvature
C. Velocity

Answers

Answer:

F = M v^2 / R = M w^2 R      where w represents the angular frequency

Only 1 / R causes a reduction in centripetal force when increased

(B)   is the answer

Option B. The radius of curvature causes a reduction in centripetal force with an increase in the magnitude.

Centripetal force is a force that acts on the object that moves in a circular motion and is directed towards the center of the circular moving path. The mathematical representation of centripetal force is -

[tex]F_{c} = \frac{mv^{2} }{r}[/tex],

Where Fc = the centripetal force,

m = mass of the object,

v = velocity

and r = radius.

From the given explanation above, The centripetal force and radius of curvature are inversely proportional to each other,

that is, Fc = 1/r.

Therefore, an increase in the radius of curvature leads to a reduction in the centripetal force.

Learn more about centripetal force:

https://brainly.com/question/11324711

AYUDA!!!!!




Si 300 cm de alcohol tienen una masa de 237 g
calcular:
a) El valor de su densidad expresada en g/cm'y en kg/m?
b) su peso específico expresado en N/m?

Answers

Answer:

a) El valor de la densidad es 0.79 [tex]\frac{g}{cm^{3} }[/tex] o 790 [tex]\frac{g}{cm^{3} }[/tex]

b) El peso especifico es 7749.9[tex]\frac{N}{m^{3} }[/tex]

Explanation:

a) La densidad se define como la propiedad que tiene la materia, ya sean sólidos, líquidos o gases, para comprimirse en un espacio determinado. En otras palabras, la densidad es una magnitud que permite medir la cantidad de masa que hay en determinado volumen de una sustancia. Entonces, la expresión para el cálculo de la densidad es el cociente entre la masa de un cuerpo y el volumen que ocupa:

[tex]d=\frac{m}{V}[/tex]

En este caso:

masa= 237 g= 0,237 kg (siendo 1000 g= 1 kg)volumen= 300 cm³= 0,0003 m³ (siendo 1 cm³= 0,000001 m³)

Reemplazando:

[tex]d=\frac{237 g}{300cm^{3} }[/tex] →  d=0.79 [tex]\frac{g}{cm^{3} }[/tex]

[tex]d=\frac{0,237 kg}{0,0003m^{3} }[/tex]→  d=790 [tex]\frac{g}{cm^{3} }[/tex]

El valor de la densidad es 0.79 [tex]\frac{g}{cm^{3} }[/tex] o 790 [tex]\frac{g}{cm^{3} }[/tex]

b) El peso específico es la relación existente entre el peso y el volumen que ocupa una sustancia en el espacio.

Entonces, en este caso, siendo el peso:

P= m*g= 0,237 kg* 9,81 [tex]\frac{m}{s^{2} }[/tex]= 2,32497 N

el peso especifico es calculado como:

[tex]Pe=\frac{Peso}{Volumen}= \frac{2,32497N}{0,0003 m^{3} }[/tex]

Pe= 7749.9[tex]\frac{N}{m^{3} }[/tex]

El peso especifico es 7749.9[tex]\frac{N}{m^{3} }[/tex]

Count how many significant figures each of the quantities below has:
a. 2.590 km
b.12.303 ml
c. 7800kg​

Answers

a. 3 sigfigs
b. 5 sigfigs
c. 2 sigfigs

* ending zeros do not count as significant figures (no matter if they are behind a decimal point or not. ex: 40 has 1 sigfig.)

* but zeros between digits always count!

Two resistors ( 3 ohms & 6 ohms) in a series circuit with a power supply = 12 volts. The current through resistor 6 ohms is :

a.
1.33 A

b.
2.66 A

c.
12 A

Answers

In a series circuit . . .

-- The total resistance is the sum of the individual resistors.

-- The current is the same at every point in the circuit.

The total resistance in this circuit is (3Ω + 6Ω )  =  9Ω

The current at every point is (V/R) = (12v / 9Ω ) = 1.33 A .

Pick choice (a).

The current flowing through the 6 Ohms resistor is: a.  1.33 A

Given the following data:

Resistor A = 3 Ohms.Resistor B = 6 Ohms.Voltage = 12 Volts.

To find the current flowing through the 6 Ohms resistor:

First of all, we would determine the total equivalent resistance of the resistors connected in series.

[tex]T_eq = Resistor \; A + Resistor\; B\\\\T_eq = 3 + 6[/tex]

Total equivalent resistance = 9 Ohms

Note: The current flowing through both resistors are the same since they are connected in series.

From Ohm's law, we have:

[tex]Current = \frac{Voltage}{Resistor}\\\\Current = \frac{12}{9}[/tex]

Current = 1.33 Amperes

Therefore, the current flowing through the 6 Ohms resistor is 1.33 Amperes.

Lex launched a golfball with his lego catapult. It traveled 7 meters and was in the air for 2 seconds. Please determine the object’s maximum height, horizontal velocity, vertical velocity, actual velocity, and time it reached its maximum height. The angle of release (the catapult’s arm) is 40°.


Horizontal Velocity = vx
Vertical Velocity = V1y
Actual Velocity: V1 = Vactual
Time reached highest point
Height reached!= h
Givens:

dx=

a=

t=


Angle of release:



Table B:
What you need to determine
Formula used
Answer: remember to label the correct units
Distance
Measure it with a meter stick


Time Traveled
Measure it with a stopwatch


Horizontal Velocity




Vertical Velocity




Actual Velocity




Time reached Highest Point




What was the object’s highest point

Answers

Answer:

Explanation:

Range R = 7 m

angle of projection θ = 40⁰

u² sin2θ / g = R where u is velocity of throw.

u² sin 80 / g = 7

u² = 69.71

u = 8.35 m/s

horizontal velocity = u cos 40 = 8.35 cos 40

= 6.4 m /s

vertical velocity = u sin 40 = 8.35 sin40

= 5.37 m /s

Maximum height :-

v² = u² - 2gh , u is initial vertical component of throw.

0 = 5.37² - 2 x 9.8 x h

h = 1.47 m

Time to reach max height :--

v = u - gt

o = 5.37 - 9.8 t

t = .55 s

i need this literally asap

which of these statements are true?
1. it is always correct to use a 3 Amp fuse.
2. Fuses come in several different sizes and values
3. A fuse can be re-set and used again
4. A fuse once ‘blown’ needs replacing
5. Fuses are the ‘weak point’ in a circuit

Answers

Answer:

I only know number 4 is correct

Explanation:

can someone explain how to find the tangent line of something :D

Answers

Answer:

This can help you! Pictures tell more than 100s of word.

Explanation:

PLEASE HELP ASAP!!!!
Motion is described with respect to what?
А
displacement
B
frame of reference
C
graph
D
speed

Answers

Answer:

Option B is correct

Explanation:

Motion is described with respect to frame of reference.

A frame of reference refers to a set of coordinates that helps to find positions and velocities of objects in the frame.

The laws of motion might be more complex than required if the coordinates are not chosen properly.

Therefore,

Option B is correct

what specific heat of water explains why the climate doesn't vary much with season in places near large body water​

Answers

Answer:

The specific heat of water is greater than that of dry soil, therefore water both absorbs and releases heat more slowly than land. ... This causes land areas to heat more rapidly and to higher temperatures and also cool more rapidly and to lower temperatures, compared to oceans.

Explanation:

A 4.00-m-long, 470 kg steel beam extends horizontally from the point where it has been bolted to the framework of a new building under construction. A 75.0 kg construction worker stands at the far end of the beam. For the steps and strategies involved in solving a similar problem, you may view a Video Tutor Solution. What is the magnitude of the torque about the point where the beam is bolted into place?

Answers

Answer:

12164.4 Nm

Explanation:

CHECK THE ATTACHMENT

Given values are;

m1= 470 kg

x= 4m

m2= 75kg

Cm = center of mass

g= acceleration due to gravity= 9.82 m/s^2

The distance of centre of mass is x/2

Center of mass(1) = x/2

But x= 4 m

Then substitute, we have,

Center of mass(1) = 4/2 = 2m

We can find the total torque, through the summation of moments that comes from both the man and the beam.

τ = τ(1) + τ(2)

But

τ(1)= ( Center of m1 × m1 × g)= (2× 470× 9.81)

= 9221.4Nm

τ(2)= X * m2 * g = ( 4× 75 × 9.81)= 2943Nm

τ = τ(1) + τ(2)

= 9221.4Nm + 2943Nm

= 12164.4 Nm

Hence, the magnitude of the torque about the point where the beam is bolted into place is 12164.4 Nm

Four identical metallic objects carry the following charges 1.82 6.65 4.80 and 9.30 C The objects are brought simultaneously into contact so that each touches the others Then they are separated a What is the final charge on each object b How many electrons or protons make up the final charge on each object

Answers

Answer:

a) 5.64 C

b) 3.5*10¹⁹ protons

Explanation:

a)

Since the four metallic objects are identical, and total charge must be conserved, this means that after brought simultaneously into contact so that each touches the others, once separated, total charge must be the same than before being brought in contact.But due they are identical, after charges were able to transfer freely between them, the four objects must have the same final charge, i.e. the fourth part of the total charge, as follows:

       [tex]Q_{n} = \frac{Q_{tot}}{4} = \frac{22.57C}{4} = 5.64 C (1)[/tex]

b)

This charge will be divided between n protons, since the charge is positive.Since each proton carries a charge equal to the elementary charge e, which value is 1.6*10⁻¹⁹ C, we can find the number of protons in excess, doing the following calculation: [tex]n_{p} =\frac{Q_{n}}{e} = \frac{5.64C}{1.6e-19C} = 3.5 e19 C (2)[/tex]

a toy train is moved towards a magnet that cannot move. what happens to the potential energy in the system of magnets during the movement​

Answers

Answer:

Dakota moves a magnetic toy train toward a magnet that cannot move. What happens to the potential energy in the system of magnets during the movement? The potential energy increases because the train moves against the magnetic force. The potential energy decreases because the train moves against the magnetic force.

I hope this helps you :)

Part A: A group of students performed the same "Ohm's Law" experiment that you did in class. They obtained the following results:
Trial V (volts) I (mA)
1 1.00 7.2
2 2.10 14.0
3 3.10 20.7
4 4.00 27.2
5 4.90 32.2
Determine the slope and y-intercept of the graph, and report these values below. (
Part B: Your mischievous lab partner takes the resistor that you just experimented with and assembles it in a network with one other resistor and places them inside a black box. He challenges you to tell him the configuration of the resistors inside the box. Being an industrious physics student you connect the leads of the black box to your power source, voltmeter (in parallel), and ammeter (in series) and take the following simultaneous measurements. Use the measurements to find the equivalent resistance of the arrangement.
V (volts) I (mA)
2.0 5.5
Part C: Now that you've answered his challenge, your lab partner asks you to give the resistance of the resistor that he added to the one you experimented with. Using the information you obtained in parts A and B, predict this value of the resistance of the second resistor.

Answers

Answer:

Kindly check explanation

Explanation:

Given the data:

Trial V (volts) I (mA)

1 1.00 7.2

2 2.10 14.0

3 3.10 20.7

4 4.00 27.2

5 4.90 32.2

Slope = Rise / Run

Rise = y2 - y1 = 32.2 - 7.2 = 25

Run = x2 - x1 = 4.9 - 1.0 = 3.9

Slope = 25 / 3.9 = 6.410

y = mx + c

The intercept, c

Take the point ( 1; 7.2)

Put x = 0

7.2 = 6.410(1) + C

7.2 - 6.410 = C

C = 0.79

Find the polar angle (in radians with respect to +x-axis) of −3i + j.

Answers

Answer:

[tex]-18.43^{\circ}[/tex]

Explanation:

Let [tex]\theta[/tex] be the polar angle of −3i + j. We can find it using the formula as follows :

[tex]\tan\theta=\dfrac{y}{x}\\\\\tan\theta=\dfrac{1}{-3}\\\\\theta=\tan^{-1}(\dfrac{1}{-3})\\\\\theta=-18.43^{\circ}[/tex]

So, the required polar angle is [tex]-18.43^{\circ}[/tex].

There are three main types of nerve fibers that carry neural signals from pain receptors to the spinal cord.


Please select the best answer from the choices provided

T
F

Answers

Answer:

true is the answer

ok false is wrong

Answer:

Not sure, but I think its T

Explanation:

How is biochar produced?

Answers

Answer:

Biochar is produced by heating biomass in the total or partial absence of oxygen. Pyrolysis is the most common technology employed to produce biochar, and also occurs in the early stages of the combustion and gasification processes. Besides biochar, bio-oil and gas can be collected from modern pyrolysers.

Who was the first scientist to explore the moon with a telescope? A Isaac Newton B Johannes Kepler C Nicolaus Copernicus D Galileo Galilae​

Answers

Answer:

D Galileo Galilae

Explanation:

It's now understood that English astronomer Thomas Harriot, (1560-1621) made the first recorded observations of the Moon through a telescope, a month before Galileo

Answer: Galileo Galilae

Explanation:

Consider the situation||: A child pulls a sled by a rope across the lawn at a constant speed. Of the forces listed, identify which act upon the sled.
Normal, Gravity, Applied, Friction, Tension, & Air Resistance

Answers

Answer:

Gravitational

Tension

Normal

Friction.

Explanation:

The forces acting on the sled are:

Tension: the tension from the rope, this is the force that "moves" the sled.

Friction: kinetic friction between the sled and the ground as the sled moves.

There are another two forces that also act on the sled, but that "has no effect"

Gravitational force: This force pulls the sled down, against the floor.

Normal force: This force "opposes" to the gravitational one, so they cancel each other.

These two forces cancel each other, so they have no direct impact on the movement of the sled. BUT, the friction force depends on the weight of the moving object, and the weight of the moving object depends on the gravitational force, so we need gravitational force in order to have friction force.

Then we can conclude that the forces acting on the sled are:

Gravitational

Tension

Normal

Friction.

For these pictures is more or less friction needed?

Answers

Answer:

8: More

9: More

10: More

11: Less

12: Less

12: More

PLEASE HELP!!!! ITS URGENT!!!

Answers

Answer:

dude the answer is upright

A 52 kg and a 95 kg skydiver jump from an airplane at an altitude of 4750 m, both falling in the pike position. Assume all values are accurate to three significant digits. (Assume that the density of air is 1.21 kg/m3 and the drag coefficient of a skydiver in a pike position is 0.7.) If each skydiver has a frontal area of 0.14 m2, calculate their terminal velocities (in m/s). 52 kg skydiver m/s 95 kg skydiver m/s How long will it take (in s) for each skydiver to reach the ground (assuming the time to reach terminal velocity is small)

Answers

Answer: 52 kg skydiver: 9.09 m/s and 522.55 s

              95 kg skydiver: 12.3 m/s and 386.2 s

Explanation: Drag Force is an opposite force when an object is moving in a fluid.

For skydivers, when falling through the air, the forces acting on it are gravitational and drag forces. At a certain point, drag force equals gravitational force, which is constant on any part of the planet, producing a net force that is zero. Since there is no net force, there is no acceleration and, consequently, velocity is constant. When that happens, the person reached the Terminal Velocity.

Drag Force and Velocity are proportional to the squared speed. So, terminal velocity is given by:

[tex]F_{G}=F_{D}[/tex]

[tex]mg=\frac{1}{2}C \rho Av_{T}^{2}[/tex]

[tex]v_{T}=\sqrt{\frac{2mg}{\rho CA} }[/tex]

where

m is mass in kg

g is acceleration due to gravitational force in m/s²

ρ is density of the fluid in kg/m³

C is drag coefficient

A is area of the object in the fluid in m²

Calculating:

The 52kg skydiver has terminal velocity of:

[tex]v_{T}=\sqrt{\frac{2(52)(9.8)}{(1.21)(0.7)(0.14)} }[/tex]

[tex]v_{T}=[/tex] 9.09

The 95kg skydiver's terminal velocity is

[tex]v_{T}=\sqrt{\frac{2(95)(9.8)}{(1.21)(0.7)(0.14)} }[/tex]

[tex]v_{T}=[/tex] 12.3

The 52 kg and 95kg skydivers' terminal velocity are 9.09m/s and 12.3m/s, respectively.

The time each one will reach the floor will be:

52 kg at 9.09 m/s:

[tex]t=\frac{4750}{9.09}[/tex]

t = 522.5

95 kg at 12.3 m/s:

[tex]t=\frac{4750}{12.3}[/tex]

t = 386.2

The 52 kg and 95kg skydivers' time to reach the floor are 522.5 s and 386.2 s, respectively.

Scott travels north 3 Km and then goes west 3 Km before coming straight
back south 3 km. What is his displacement? *
9 Km
3 km, W
3 Km, E
9 km, S

Answers

Answer:

you have to times them all ti get the answer

An atom has 13 protons in its nucleus and 11 electrons revovling the nucleus. The charge on this atom:

a.
The atom has no charge .

b.
+2

c.
-2

d.
+1

Answers

The atoms has no charge so A would be the answer.

Particle A and particle B are held together with a compressed spring between them. When they are released, the spring pushes them apart, and they then fly off in opposite directions, free of the spring. The mass of A is 8.00 times the mass of B, and the energy stored in the spring was 73 J. Assume that the spring has negligible mass and that all its stored energy is transferred to the particles. (a) Once that transfer is complete, what is the kinetic energy of particle A

Answers

Answer:

 K_a = 8,111 J

Explanation:

This is a collision exercise, let's define the system as formed by the two particles A and B, in this way the forces during the collision are internal and the moment is conserved

initial instant. Just before dropping the particles

          p₀ = 0

final moment

          p_f = m_a v_a + m_b v_b

          p₀ = p_f

          0 = m_a v_a + m_b v_b

tells us that

          m_a = 8 m_b

         

           0 = 8 m_b v_a + m_b v_b

           v_b = - 8 v_a                    (1)

indicate that the transfer is complete, therefore the kinematic energy is conserved

starting point

           Em₀ = K₀ = 73 J

final point. After separating the body

          Em_f = K_f = ½ m_a v_a² + ½ m_b v_b²

           K₀ = K_f

           73 = ½ m_a (v_a² + v_b² / 8)

           

we substitute equation 1

           73 = ½ m_a (v_a² + 8² v_a² / 8)

           73 = ½ m_a (9 v_a²)

           73/9 = ½ m_a (v_a²) = K_a

            K_a = 8,111 J

When heat travels between two objects that are touching, it is moving by ________

radiation
convection
conduction
none of the above

Answers

When heat travels between two objects that are touching,

it is moving by conduction.

select the correct answer
In which disorder does a person find it difficult to fall
asleep ot stay asleep for a long time
A. somnambulism
B. narcolepsy
C. insomnia
D. sleep apnea

Answers

Answer:

insomnia

I think it is option C.

hope it helps

The correct answer is C
The definition of insomnia is a common sleep disorder that can make it hard to fall asleep, hard to stay asleep, or cause you to wake up and not be able to go back to sleep

What is the momentum of a compact car that is 750 kg and is travelling 30 m/s?

Answers

The formula for momentum is p = mv, where p is momentum, m is mass, and v is velocity.

To solve for p, plug in 750 kg for mass and 30 m/s for velocity. • is a multiplication symbol

p = mv
p = 750kg • 30m/s
p = 22500 kg•m/s

The momentum of a compact car that is 750 kg and is travelling 30 m/s be 22500 N-s.

What is momentum?

The relationship between a particle's mass and velocity is called momentum. Being a vector quantity, momentum possesses both magnitude and direction. According to Isaac Newton's second equation of motion, the force applied on a particle is equal to the time rate of change of momentum.

Given parameters:

Mass of the compact car: m = 750 kg.

Speed of the car: v = 30 m/s.

Hence, magnitude of momentum of the car is = mv

= 750×30 N-s

= 22500 N-s.

Learn more about momentum here:

https://brainly.com/question/29113044

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