A battery has am emf of 15 V and internal resistance of 1Ω. In the terminal potential difference less than, equal to or greater than 15V if the current in the battery is (i) from negative to positive terminal, (ii) from positive to negative terminal (iii) zero current ?
a. Less, Greater, Equal
b. Less, Less, Equal
c. Greater, Greater, Equal
d. Greater, Less, Equal

Answer:

12000N

Explanation:

gravity on earth is six times one on the moon

Answer:

true:)

Explanation:

Part A :The position of the particle in vector form is given by[tex]r⃗ (t)=R[cos(ωt)i^+sin(ωt)j^][/tex]where R is the radius of the circle and ω is the angular velocity.The velocity of the particle is given by taking the derivative of the position vector with respect to time.

Taking derivative with respect to time on both side we get [tex]v⃗ (t)=d/dt R[cos(ωt)i^+sin(ωt)j^]= R[-in(ωt)ωi^+cos(ωt)ωj^]=ωR[-sin(ωt)i^+cos(ωt)j^]v⃗ (t)=ωR[-sin(ωt)i^+cos(ωt)j^][/tex]Thus the velocity of the mass at a time t is given by [tex]v⃗ (t)=ωR[-sin(ωt)i^+cos(ωt)j^][/tex].

Part B :

We have to find the velocity at time -t. The velocity of the particle is given by taking the derivative of the position vector with respect to time. Thus the velocity of the mass at a time -t is given by [tex]v⃗ (-t) = ωR[sin(ωt)i^ - cos(ωt)j^][/tex]

[tex]v⃗ (-t) = ωR[sin(ωt)i^ - cos(ωt)j^][/tex]Part C :

The average acceleration of the particle can be computed using the formulaa = [tex]Δv/Δt[/tex]The velocity at time t is given by[tex]v⃗ (t) = ωR[-sin(ωt)i^+cos(ωt)j^][/tex]

The velocity at time -t is given by [tex]v⃗ (-t) = ωR[sin(ωt)i^ - cos(ωt)j^][/tex]

[tex]v⃗ (-t) = ωR[sin(ωt)i^ - cos(ωt)j^][/tex]The change in velocity over the interval from -t to t is therefore

[tex]Δv = v(t) - v(-t) = 2ωR[sin(ωt)i^ + cos(ωt)j^][/tex]

The time interval over which this change occurs is[tex]Δt = 2t[/tex]Thus the average acceleration of the particle is given by a = [tex]Δv/Δt = ω^2R[sin(ωt)i^ + cos(ωt)j^]/t[/tex]

[tex]a = Δv/Δt = ω^2R[sin(ωt)i^ + cos(ωt)j^]/t[/tex]

The acceleration can be expressed in terms of R, ω, t, and the unit vectors [tex]i^ and j^[/tex] as [tex]a = ω^2R[sin(ωt)i^ + cos(ωt)j^]/t[/tex].

To know more about angular velocity visit :

https://brainly.com/question/30237820

#SPJ11

Kinetic energy refers to the energy possessed by an object due to its motion. The formula for kinetic energy is given as follows: Kinetic energy = 1/2 × mass × velocity², Where: mass = the mass of the object, velocity = the speed of the object.

We can equate the kinetic energies of the car and truck using the formula above. Let's assume that the speed of the car is v. Therefore, we can write:1/2 × 1800 × v² = 1/2 × 1.80×10⁴ × (25/3.6)², Where:25/3.6 is used to converting the speed of the truck from km/h to m/s.

Simplifying the right-hand side of the equation, we get:1/2 × 1.80×10⁴ × (25/3.6)² = 781250 J.

Now, we can solve for v by dividing both sides of the equation by 1/2 × 1800:1/2 × 1800 × v² = 781250v² = 781250 ÷ 900v² = 868.056v ≈ 29.47 m/s.

Therefore, the speed at which an 1800 kg compact car has the same kinetic energy as a 1.80×10⁴ kg truck going 25.0 km/h is approximately 29.47 m/s.

Learn more about Kinetic energy here ;

https://brainly.com/question/999862

#SPJ11

Answer:

the velocity component parallel to the magnetic field vector

Explanation:

When a charged particle moves in a helical path, we can decompose its velocity into two parts v_parallel and v_perpendicular to the magnetic field.

Let's analyze which component receives a force

            F = q vxB

the bold letters indicate vectors, in the vector product if the two vectors are parallel the angle is zero and the sin 0 = 0 for which there is no force. therefore the velocity parallel to the field remains constant

If the two vectors are perpendicular, the angle is 90º and the sin 90 = 1, for which there is a force, which has a radial direction and consequently a centripetal acceleration that gives a circular path that does not remove the particle from the magnetic field

When checking the different answers, the correct one is: the velocity component parallel to the magnetic field vector

The maximum velocity of the particle is 100 m/s. Negative sign indicates that the velocity is in the opposite direction of the displacement at that particular point in time.

To find the maximum velocity of a particle in simple harmonic motion, we need to differentiate the position function with respect to time and then find the maximum value of the resulting velocity function.

Given the position function x = 2cos(50t), we can find the velocity function v(t) by taking the derivative of x with respect to t:

v(t) = dx/dt = -2(50)sin(50t) = -100sin(50t)

The maximum velocity occurs when the sine function has a maximum value of 1. Therefore, the maximum velocity can be found by evaluating the velocity function at that point. In this case, the maximum value of sin(50t) is 1 when 50t = π/2 or t = π/100.

Substituting t = π/100 into the velocity function:

v_max = -100sin(50(π/100)) = -100sin(π/2) = -100(1) = -100 m/s

Therefore, the maximum velocity of the particle is 100 m/s. Note that the negative sign indicates that the velocity is in the opposite direction of the displacement at that particular point in time.

To know more about simple harmonic motion

https://brainly.com/question/26114128

#SPJ4

The female whale is approximately 3,000 meters away from the male whale.

To calculate the distance between the male and female blue whales, we can use the formula:

Distance = (Speed of sound in water × Time) / 2

Given that the speed of sound in water is approximately 1,500 m/s and the time taken for the sound to return is 4 seconds, we can substitute these values into the formula:

Distance = (1,500 m/s × 4 s) / 2

Simplifying the equation:

Distance = (6,000 m) / 2

Distance = 3,000 m

For more such questions on whale,click on

https://brainly.com/question/19852583

#SPJ8

A balanced equation is a chemical equation in which the number of atoms of each element on both sides of the equation is equal. It represents a chemical reaction, indicating the reactants and products involved and the stoichiometric relationship between them.

The balanced equation for the reaction between RbNO3 and BeF2 is: 2RbNO3 + BeF2 → Be(NO3)2 + 2RbF.

To check if the equation is balanced or not, we can count the number of atoms of each element on both sides of the equation.

Here, we have Rb: 2 on both sides,  N: 2 on both sides, O: 6 on both sides, Be: 1 on both sides, F: 2 on both sides.

Therefore, the balanced equation for the reaction between RbNO3 and BeF2 is 2RbNO3 + BeF2 → Be(NO3)2 + 2RbF, which has the correct products for the given reactants.

Learn more about balanced equation here ;

https://brainly.com/question/31242898

#SPJ11

Answer:There are two main types of friction, static friction and kinetic friction. Static friction operates between two surfaces that aren't moving relative to each other, while kinetic friction acts between objects in motion.

To observe asteroids: Calculate and improve orbits. Know about asteroids. Identify characteristics of asteroids. Take samples from asteroids. Identify asteroids a threat to life on earth. The correct answers are A, B, C, D, and E.

Observing asteroids allows us to:

A. Calculate and improve current calculations of their orbits: By observing their positions and movements over time, we can refine our understanding of their orbits, predict future positions, and assess potential collision risks.

B. Know more about the composition of asteroids: By analyzing their reflected light, emission spectra, and studying meteorites that originate from asteroids, we can gain insights into their mineralogical and chemical compositions, helping us understand the formation and evolution of the solar system.

C. Identify characteristics of asteroids such as if they have rings or tails: Through careful observations, we can detect features like rings or tails associated with certain asteroids, providing valuable information about their structure and behavior.

D. Take samples of materials from asteroids: By sending spacecraft missions to asteroids, we can collect samples from their surfaces or even perform asteroid deflection experiments, enabling us to study their physical properties and potential resources.

E. Identify asteroids that represent a threat to life on Earth: Continuous monitoring and observation of asteroids allow us to identify and track potentially hazardous asteroids that may pose a risk of impacting Earth, enabling us to plan and develop mitigation strategies if necessary.

Therefore, observing asteroids contributes to a wide range of activities, from refining orbital calculations and understanding their composition and characteristics to assessing potential threats and even collecting samples from them.The correct answers are A, B, C, D, and E.

To know more about asteroids, refer here:

https://brainly.com/question/29609638#

#SPJ11

Explanation:

With most of our blue planet covered by water, it's little wonder that, centuries ago, the oceans were believed to hide mysterious creatures including sea serpents and mermaids. Merfolk (mermaids and mermen) are, of course, the marine version of half-human, half-animal legends that have captured human imagination for ages. One source, the "Arabian Nights," described mermaids as having "moon faces and hair like a woman's but their hands and feet were in their bellies and they had tails like fishes."

C.J.S. Thompson, a former curator at the Royal College of Surgeons of England, notes in his book "The Mystery and Lore of Monsters" that "Traditions concerning creatures half-human and half-fish in form have existed for thousands of years, and the Babylonian deity Era or Oannes, the Fish-god ... is usually depicted as having a bearded head with a crown and a body like a man, but from the waist downwards he has the shape of a fish." Greek mythology contains stories of the god Triton, the merman messenger of the sea, and several modern religions including Hinduism and Candomble (an Afro-Brazilian belief) worship mermaid goddesses to this day.

When light travels from air into water through an oil film, several optical phenomena come into play: refraction, reflection, and interference.

First, refraction occurs at the air-water interface. As light enters the water, it undergoes a change in speed and direction due to the change in the refractive index between the two mediums. This causes the light to bend or deviate from its original path. Next, reflection occurs at the interface between the water and the oil film. A portion of the light is reflected back into the water, following the law of reflection. The angle of incidence is equal to the angle of reflection.

Interference also plays a role in this scenario. When the light waves reflect off the oil film, they can interfere constructively or destructively depending on their phase relationship. This interference can result in the appearance of colorful patterns, commonly known as thin-film interference. The colors observed in the oil film are due to the constructive and destructive interference of different wavelengths of light. The thickness of the oil film determines which wavelengths interfere constructively and produce visible colors.

Learn more about refractive index here:

https://brainly.com/question/30761100

#SPJ11

The ranking of the  work done by the torque is a > b > c > d.

The work done by the torque is equal to the change in rotational kinetic energy of the body.

Mathematically, the formula for torque is given as;

τ = r.F sinθ = Iα

where;

The formula for angular acceleration is given as;

α = Δω / Δt

where;

Thus, the greater the change in angular speed, the greater the work done by the applied torque.

(a) Δω = 7 rad/s - (-3 rad/s) = 10 rad/s

(b) Δω = 7 rad/s - 3 rad/s = 4 rad/s

(c) Δω = -7 rad/s - (-3 rad/s) = -4 rad/s

(d) Δω = -7 rad/s - 3 rad/s =  -10 rad/s

The ranking, a > b > c > d

Learn more about work done here: https://brainly.com/question/8119756

#SPJ4

(a) To find the total translational kinetic energy of the gas molecules, we can use the formula: Total kinetic energy = (3/2) * N * k * T, Where: N = Avogadro's number, k = Boltzmann's constant, T = temperature in Kelvin

First, let's convert the given mass of hydrogen gas (2.0 g) into moles: Number of moles = mass / molar mass Number of moles = 2.0 g / (2.016 g/mol) ≈ 0.993 mol. Next, we need to convert the temperature in Kelvin. Since only the rms speed is provided, we can use the following equation to relate it to temperature: v(rms) = sqrt((3 * k * T) / ms. where: v(rms) = rms speed m = molar mass of the gas. Rearranging the equation, we can solve for T: T = (m * v(rms)^2) / (3 * k) Using the given rms speed of 1600 m/s and the molar mass of hydrogen gas (2.016 g/mol), we can calculate the temperature in Kelvin: T = (2.016 g/mol * (1600 m/s)^2) / (3 * (1.381 × 10^-23 J/K)) Calculating T, we find: T ≈ 7309 K. Now, we can substitute the values into the formula for total kinetic energy: Total kinetic energy = (3/2) * N * k * T Total kinetic energy = (3/2) * (0.993 mol) * (1.381 × 10^-23 J/K) * (7309 K) Calculating the total kinetic energy, we find: Total kinetic energy ≈ 2.676 × 10^-19 J, Therefore, the total translational kinetic energy of the gas molecules is approximately 2.676 × 10^-19 J. (b) The thermal energy of the gas is equal to the total translational kinetic energy since we assume the gas is monoatomic and all its energy is in the form of kinetic energy. So, the thermal energy is also approximately 2.676 × 10^-19 J. (c) To find the new rms speed of the molecules after the work and heat transfer, we can use the principle of conservation of energy: Change in thermal energy = Work done + Heat transferred. Since the change in thermal energy is given as 1200 J, we have: 1200 J = 500 J + Heat transferred. Heat transferred = 1200 J - 500 J Heat transferred = 700 J Now, we can use the equation v(rms) = sqrt((3 * k * T) / m) to find the new rms speed. Rearranging the equation, we have: v(rms) = sqrt((3 * k * T') / m) Where T' is the new temperature in Kelvin. We can solve for T' by rearranging the equation: T' = (m * v(rms)^2) / (3 * k) Substituting the values into the equation, we have: T' = (2.016 g/mol * (1600 m/s)^2) / (3 * (1.381 × 10^-23 J/K)) Calculating T', we find: T' ≈ 7309 K, Therefore, the rms speed of the molecules after the work and heat transfer is approximately 1600 m/s, the same as before.

To learn more about energy, https://brainly.com/question/14959619

#SPJ11

Answer:

3 moles

Explanation:

Ratio of O2 to CO2 = 2 : 1 = 6 : 3

Answer:

1-B, 2-A, 3-D, 4-C

Explanation:

1. The force exerted is, F = 35 N

  Distance the box is moved, d = 4 m

  So the amount of work done is, W = F x d

                                                            = 35 x 4

                                                            = 140 Newton-meters

2. Work done, W  = 420 Nm

   Time, T = 3 seconds

   Therefore, the power required is,

   [tex]$P=\frac{W}{T}$[/tex]

   [tex]$P=\frac{420}{3}$[/tex]

       = 140 joules

3. The force exerted is, F = 1.2 N

  Distance the box is moved, d = 5 m

  So the amount of work done is, W = F x d

                                                            = 1.2 x 5

                                                            = 6 Newton-meters

4. Work done, W  = 120 Nm

   Time, T = 20 seconds

   Therefore, the power required is,

   [tex]$P=\frac{W}{T}$[/tex]

   [tex]$P=\frac{120}{20}$[/tex]

       = 6 joules

When the average velocity is 2.4 m/s, the horizontal 0.35 meter diameter cast iron water pipe experiences a pressure drop (P) of roughly 16457.14 kPa every 100 meters.

To determine the pressure drop per 100-meter length of a horizontal 0.35-meter diameter cast iron water pipe, we can use the Darcy-Weisbach equation. The equation is as follows:

[tex]\begin{equation}\Delta P = \frac{f \cdot \frac{L}{D} \cdot (\rho \cdot V^2)}{2}[/tex]

where ΔP is the pressure drop, f is the Darcy friction factor, L is the length of the pipe (100 meters in this case), D is the diameter of the pipe (0.35 meters), ρ is the density of water, and V is the average velocity of water.

To calculate the pressure drop, we need to determine the Darcy friction factor. For a rough cast iron pipe, we can estimate the friction factor to be around 0.02.

Using the given values and the estimated friction factor, the calculation becomes:

[tex]\begin{equation}\Delta P = \frac{0.02 \cdot \frac{100}{0.35} \cdot (\rho \cdot 2.4^2)}{2}[/tex]

Since the density of water (ρ) is approximately 1000 kg/m³, we can substitute this value and calculate the pressure drop:

ΔP = [tex]\frac{0.02 \times \frac{100}{0.35} \times 1000 \times 2.4^2}{2}[/tex]

Let's solve the expression to calculate the pressure drop (ΔP) in kilopascals (kPa):

ΔP =  [tex]\frac{0.02 \times \frac{100}{0.35} \times 1000 \times 2.4^2}{2}[/tex]

First, let's simplify the expression:

ΔP = [tex]\frac{0.02 \times (285.714) \times (1000 \times 5.76)}{2}[/tex]

   = 16457.14

Therefore, the pressure drop (ΔP) per 100-meter length of the horizontal 0.35-meter diameter cast iron water pipe, when the average velocity is 2.4 m/s, is approximately 16457.14 kPa.

To know more about the cast iron water pipe refer here :

https://brainly.com/question/32455854#

#SPJ11

Complete question :

Determine the pressure drop per 100 -m length of horizontal new 0.35−m-diameter cast iron water pipe when the average velocity 2.4 m/s. Δp= kPa

The energy contained in a 1.0 m length of the beam from a 7.7 mW laser is 7.7 μJ (microjoules).

To calculate the energy contained in the length of the laser beam, we need to use the power of the laser and the formula:

Energy = Power × Time

However, we don't have the time information here. To proceed, we'll assume a continuous wave laser where the power remains constant over time.

Given:

Power of the laser = 7.7 mW (milliwatts)

Length of the beam = 1.0 m

First, we need to convert the power from milliwatts to watts:

7.7 mW = 7.7 × 10^(-3) W

Next, we can calculate the energy using the formula:

Energy = Power × Time

Since we assume a continuous wave laser, we can rearrange the formula as:

Energy = Power × Time = Power × (1 second)

Plugging in the values:

Energy = (7.7 × 10^(-3) W) × (1 second)

The time in this case is 1 second because we assume a continuous beam over that duration. Multiplying the power by 1 second doesn't change the value.

Finally, we can calculate the energy:

Energy = (7.7 × 10^(-3) W) × (1 second)

= 7.7 × 10^(-3) J (joules)

Since the joule is a relatively large unit, it's common to express small energy values in smaller units such as microjoules (μJ).

Converting from joules to microjoules:

1 J = 10^6 μJ

Therefore,

Energy = 7.7 × 10^(-3) J

= 7.7 × 10^(-3) × 10^6 μJ

= 7.7 × 10^(3) μJ

= 7.7 μJ

The energy contained in a 1.0 m length of the beam from a 7.7 mW laser is 7.7 μJ (microjoules).

To learn more about energy, visit    

https://brainly.com/question/2003548

#SPJ11

The wavelength of microwaves with a frequency of 10 GHz is 0.03 meters or 3 centimeters. These microwaves cause the water molecules in the burrito to vibrate due to the absorption of their energy, resulting in the heating of the food.

The wavelength of microwaves with a frequency of 10 GHz can be calculated using the formula λ = c/f, where λ represents wavelength, c is the speed of light (3 × 10^8 m/s), and f is the frequency (10^10 Hz). Therefore, the wavelength of these microwaves is 0.03 meters or 3 centimeters.

The relationship between wavelength, frequency, and the speed of light is given by the equation λ = c/f, where λ represents wavelength, c is the speed of light, and f is the frequency. In this case, we have a frequency of 10 GHz, which is equivalent to 10^10 Hz. Plugging these values into the equation, we get:

λ = c/f

= (3 × 10^8 m/s) / (10^10 Hz)

= 3 × 10^(-2) meters

= 0.03 meters

= 3 centimeters

Learn more about wavelength of microwaves :

https://brainly.com/question/31616989

#SPJ11

Answer:

they all need a source of oxygen

Answer:

B

Explanation:

Answer:223.46 MJ

Explanation:

Given

The thermal conductivity of brick wall is [tex]k=1.16\ W/m.^{\circ}C[/tex]

Cross-section of Wall [tex]A=5\m \times 7\ m[/tex]

time period [tex]t=17.2\ h=17.2\times 60\times 60=61,920\ s[/tex]

Inside temperature [tex]T_i=24^{\circ}C[/tex]

Outside temperature [tex]T_o=8^{\circ}C[/tex]

Heat transfer through the bricks

[tex]\dot{Q}=kA\dfrac{dT}{dx}[/tex]

[tex]\dot{Q}=1.16\times 35\times \dfrac{16}{0.18}\\\\\dot{Q}=3608.88\ W[/tex]

Heat flow for 17.2 h

[tex]Q=3608.88\times 61,920=223.46\ MJ[/tex]

The frequency of light with a wavelength of 400 nm is approximately [tex]7.494 * 10^{14} Hz[/tex] (or 749.4 THz).

To calculate the frequency of light, you can use the equation:

Frequency = Speed of light / Wavelength

The speed of light in a vacuum is approximately 299,792,458 meters per second (m/s). We need to convert the given wavelength of 400 nm to meters.

[tex]1 nm = 1 * 10^{-9}[/tex] meters

Converting 400 nm to meters:

[tex]400 nm = 400 * 10^{-9} meters = 4 * 10^{-7} meters[/tex]

Now, we can calculate the frequency:

Frequency = (Speed of light) / (Wavelength)

[tex]= 299,792,458 m/s / (4 * 10^{-7} meters)\\ =7.494 * 10^{14} Hz[/tex]

Therefore, the frequency of light with a wavelength of 400 nm is approximately [tex]7.494 * 10^{14} Hz[/tex] (or 749.4 THz).

To learn more about Wavelength visit:

brainly.com/question/32201888

#SPJ11

Answer:

13,308 MAYBE IF IT ISN'T IM SO SORRY

Explanation:

When the given alkene is treated with MCPBA (meta-chloroperoxybenzoic acid), four stereoisomers are formed due to the presence of a double bond.

These stereoisomers can be classified as cis-trans isomers and enantiomers. When an alkene reacts with MCPBA, it undergoes an epoxidation reaction, resulting in the formation of an epoxide. The given alkene has a double bond between two carbon atoms, and MCPBA adds an oxygen atom across this double bond, forming an epoxide.

The first type of stereoisomer formed is the cis-trans isomers. The cis isomer refers to the arrangement where the two substituents on the same side of the double bond in the alkene remain on the same side in the resulting epoxide. The trans isomer refers to the arrangement where the substituents on the alkene's two carbons switch sides in the resulting epoxide. Thus, two cis-trans isomers are formed.

The second type of stereoisomer formed is enantiomers. Enantiomers are non-superimposable mirror images of each other. In the case of the given alkene, if the substituents attached to the double bond are different, two enantiomers are formed as a result of the epoxidation reaction.

In total, four stereoisomers are formed when the given alkene is treated with MCPBA. These stereoisomers can be identified by their different arrangements of substituents around the newly formed epoxide group.

To learn more about stereoisomers refer:

https://brainly.com/question/18120547

#SPJ11

The decay of uranium isotopes is used to provide information about the age of earth.

Answer:

The can would be heavier.

Explanation:

The more rust is on the can, (Or object) the more it weights it down.

Answer:

The answer would be heavier, though it depends upon the type of metal. Rusting is essentially corrosion. Rust is often caused by a piece of metal getting soaked in water and then being exposed to oxygen. The rust will add more weight to the can so it becomes heavier.

Answer:

Se obtienen 2,27 gramos de metanol.

Explanation:

La reacción entre monóxido de carbono e hidrógeno para producir metanol es la siguiente:

CO + 2H₂ → CH₃OH  

Para encontrar el reactivo limitante y el reactivo en exceso, debemos calcular el número de moles de CO y H₂:

[tex]\eta_{CO} = \frac{m}{M} [/tex]              

En donde:    

m: es la masa

M: es el peso molecular  

[tex]\eta_{CO} = \frac{m}{M_{CO}} = \frac{2,0 g}{28,01 g/mol} = 0,071 moles [/tex]

[tex]\eta_{H_{2}} = \frac{2,0 g}{2,02 g/mol} = 0,99 moles [/tex]

Dado que la relación estequiométrica entre CO y H₂ es 1:2, el número de moles de hidrógeno gaseoso que reaccionan con el monóxido de carbono es:

[tex] \eta_{H_{2}} = \frac{2}{1}*0,071 = 0,142 moles [/tex]      

Entonces, se necesitan 0,142 moles de H₂ para reaccionar con 0,071 moles de CO y debido a que se tienen más moles de H₂ (0,99 moles) entonces el reactivo limitante es CO y el reactivo en exceso es H₂.

Ahora podemos encontar la masa de metanol obtenida usando el reactivo limitante (CO) y sabiendo que la realcion estequiométrica entre CO y CH₃OH es 1:1.    

[tex] \eta_{CH_{3}OH} = \eta_{CO} = 0,071 moles [/tex]

[tex] m = 0,071 moles*32,04 g/mol = 2,27 g [/tex]

Por lo tanto, se obtienen 2,27 gramos de metanol.

Espero que te sea de utilidad!      

Answer:

t = 1130 s = 18.83 min

Explanation:

First, we will calculate the energy required to evaporate 500 g of water:

[tex]E = mL[/tex]

where,

E = Energy Required for evaporation of water =?

m = mass of water = 500 g = 0.5 kg

L = Latent heat of vaporization of water = 2.26 MJ/kg = 2260 KJ/kg

Therefore,

[tex]E = (0.5\ kg)(2260\ KJ/kg)\\E = 1130\ KJ[/tex]

Now, we will calculate the time required:

[tex]P = \frac{W}{t}\\\\t = \frac{W}{P}[/tex]

where,

t = time = ?

P = Power of kettle = 1 KW

Therefore,

[tex]t = \frac{1130\ KJ}{1 KW}\\\\[/tex]

t = 1130 s = 18.83 min