An air-filled parallel-plate capacitor of capacitance C is connected to a battery and charged to a voltage V. The capacitor is then disconnected from the battery. If the distance between the capacitor plates is halved while the charge on the capacitor remains the same, which of the following is true?

The conductivity of the substance containing free electrons is calculated to be 7.59 × 10⁹ siemens/m or mho.

Number of free electrons is given as 9 × 10³⁰

Collision time is given as 3 × 10⁻¹⁴ s

Mass of electron is known to be = 9.1 × 10⁻³¹ kg

Charge on electron = 1.6 × 10⁻¹⁹ C

Conductivity of the substance is given by the formula,

σ = (n e² τ)/m

where,

σ is conductivity

n is number of electrons

m is mass of electron

e is charge of electron

τ is time

Putting in the values in the above equation, we have,

σ = [(9 × 10³⁰)(1.6 × 10⁻¹⁹)² (3 × 10⁻¹⁴)]/(9.1 × 10⁻³¹) = (69.12× 10⁻²²)/(9.1 × 10⁻³¹) = 7.59 × 10⁹ siemens/m.

To know more about electrons:

https://brainly.com/question/27994070

#SPJ4

Answer:

A1 = π R^2        original area

A2 = π (R + ΔR)^2        area of hole increased in radius by ΔR

A2 - A1 = π (2 R ΔR + ΔR^2) change in area due to heating

Δ A = π 2 R ΔR           ΔR^2 is small and will be omitted

ΔR = R c ΔT        where ΔT is the temperature change

Thus the coefficient of area expansion is twice that of the coefficient of linear expansion

Answer:

45 km per hour due east

Explanation:

it has bot magnitude and direction

Answer:

the force F2 has a magnitude of 45.5 N and a direction of 128.7° counterclockwise from the x-axis

Explanation:

To determine the second force (F2), we can use vector addition.

Starting from F1=25 N west, we add F2 in the opposite direction of the resultant (40 N south) until the vectors sum to the desired resultant:

F1 + F2 = 40 N south

25 N west + F2 = 40 N south

To find F2, subtract F1 from both sides:

F2 = 40 N south - 25 N west

Using the Pythagorean theorem, the magnitude of F2 can be found as follows:

F2 = √(F2x^2 + F2y^2) = √((-25)^2 + 40^2) = √(625 + 1600) = √2125 = 45.5 N

The direction of F2 can be found using inverse tangent:

Θ = atan2(F2y, F2x) = atan2(40, -25) = 128.7° (measured counterclockwise from the x-axis)

The roots of given equations can be solved by calculus and the intersection of the 3 equations are at the origin i.e (0,0)

The roots of x=tan(x) :

The solution is the x-value of the point of intersection.

x = 69.05396782n, 4.49340945+69.05396782n,7.72525183+69.05396782n,14.06619391+

69.05396782n,20.37130295+69.05396782n,26.66605425 +69.05396782n,42.38791356 +69.05396782n

, for any integer n

Graph the line using the slope and y-intercept, or two points.

Slope:

1

y-intercept: (0,0)

x          y

0         0

1           1

Graph the trigonometric function using the amplitude, period, phase shift, and vertical shift.

Vertical Asymptotes: x = pi/2 + pi.n ,for any integer n

Amplitude: None

Period: π

Therefore, the intersection is origin here.

Learn more about the roots of an equation here :

https://brainly.com/question/12029673

#SPJ4

The correct answer is A)greater than your normal weight at rest.

When an elevator moves upward, the passengers inside experience a change in their gravitational potential energy. According to the law of conservation of energy, the change in potential energy must be compensated by an equal and opposite change in some other form of energy, such as kinetic energy or thermal energy.

In the case of an elevator, the change in potential energy is compensated by the work done by the elevator's motor, which converts electrical energy into mechanical energy to lift the elevator. The passengers inside the elevator do not experience any change in their weight, as they are still subject to the same gravitational force. However, they do experience a change in their relative position with respect to the Earth's surface, which can result in changes in their apparent weight.

In addition to the change in potential energy, the passengers inside the elevator may also experience changes in their kinetic energy and thermal energy due to the motion of the elevator.

Therefore, The correct answer is A)greater than your normal weight at rest.

To know more about gravitational force refer to:

brainly.com/question/24783651

#SPJ4

The average power required by a 1000 kg speedboat to go from rest to 20.0 m/s in 5.00 s is 60000 Watts.

The average power required to accelerate an object is equal to the force required to overcome resistance multiplied by the velocity gained. In this case, the drag force fd opposes the acceleration of the speedboat, and so the net force on the boat is equal to the difference between the force applied to the boat and the drag force:

Fnet = Fapplied - fd = ma - fd

where m is the mass of the boat (1000 kg) and a is the acceleration. The acceleration can be calculated from the velocity gained and the time taken:

a = (vf - vi) / t = (20 m/s - 0 m/s) / 5.00 s = 4 m/s^2

So, the net force is:

Fnet = ma - fd = 1000 kg * 4 m/s^2 - 500 N = 3000 N

The power required to overcome the drag force and accelerate the speedboat is equal to the net force multiplied by the velocity gained:

P = Fnet * v = 3000 N * 20 m/s = 60000 Watts

Therefore, the average power required is 60000 Watts.

To know more about average power please refer:

https://brainly.com/question/17008088

#SPJ4

Over 118 elements have been identified and placed on the periodic table, including unstable elements made artificially in accelerators. Since 1993, a number of new elements have been discovered or synthesized in the laboratory, but the exact number may have changed.

There are more than 118 components in the occasional table, including some that were made falsely in labs. This number has expanded since the time the DOE handbook was written in 1993. The disclosure of new components is a continuous interaction, and researchers are continually attempting to find and recognize new components. Nonetheless, it's difficult to give a precise number of the number of new components that have been found starting around 1993, as the field of science is continuously developing and new disclosures are being made. In this way, any reasonable person would agree that the occasional table has extended starting around 1993, and more components might be included what's in store.

To learn more about different elements, refer:

https://brainly.com/question/3773555

#SPJ4

A week after full moon, the moon's phase is third quarter.

In its spherical form, the moon completes one orbit of the Earth every 29.5 days. It's being lit up by the sun from all sides as it rotates. When the moon is in its "new moon" position between the Earth and the Sun, the side of the moon that is facing us is completely in the dark, and is only dimly illuminated by sunlight reflected from the Earth. The side of the Moon that we can see from Earth grows increasingly bright as it orbits the planet. The "third quarter phase" of the moon occurs exactly one week (or 21 days) after the "new moon" phase begins or seven days after full moon. The sun's light is now shining on the opposite half of the moon's visible face.

To learn more about moon's phase, click here:

https://brainly.com/question/2285324

#SPJ4

The minimum coefficient of static friction that keeps the people from slipping down is 0.162.

Radius of the room, or radius of the rotation, R = 5.1 m

Rotation frequency, ω = 0.55 revolution/sec

ω = 2π×0.55 = 3.46 rad/sec

Then linear speed, v = rω = 5.1 × 3.46

v = 17.6 m/s

Let the mass of the person, = m

Let the minimum coefficient of static friction, = μ

Wall reaction will provide the normal reaction, N = mv²/r

Weight of the person will be balanced by the friction force, mg = μN

μmv²/r = mg

μ = rg/v²

μ = 5.1×9.81/17.6²

μ = 0.162

To know more about static friction, here

https://brainly.com/question/13000653

#SPJ4

Answer:

208333 J (approx)

Explanation:

Work required to stop = Kinetic energy of car

So,

Kinetic Energy = 1/2 * m * v^2

Convert 60 kmh-1 to ms-1

= 1/2 * 1500 * (50/3)^2

= 208333.33 J

We only need to multiply 5V by the amount of current the device is drawing from the port because power is equal to current times voltage.

Although the USB port is only designed to handle electricity up to 5 A, certain manufacturers may offer a higher maximum current.

The potential difference in charge between two sites in an electrical field is quantified as voltage, also known as electromotive force.

The amount of charge carriers that pass a fixed point in a unit of time via a conducting or semiconducting medium for a certain flow resistance increases with voltage, i.e., the number of charge carriers that pass a fixed point in a unit of time.

Therefore, We only need to multiply 5V by the amount of current the device is drawing from the port because power is equal to current times voltage.

To learn more about Current, refer to the link:

https://brainly.com/question/13076734

#SPJ1

The electric force between the droplets, and the horizontal acceleration this force produce on the droplets are: 5.84*10^-7 N and 0.32 m/s² respectively

In physics the electric force is the force that attracts or repels two charges (q) separated at a distance called (r), this is expressed in the international system of units in Newton.

To solve this exercise the electric force formulas and the procedures we will use are:

Where:

Given Info:

Applying the electric force formula we have:

F = (k * q1 * q2)/r²

F = [(9 *10^9 N*m²/C² * (2.9*10^-11 C) * (2.9*10^-11 C)]/ (3.6*10^-3 m)²

F = 7.569*10^-12 N*m² /1.296*10^-5 m²

F = 5.84*10^-7 N

Applying the force formula and clearing the acceleration, we get:

a= F/m

a= 5.84*10^-7 N/ 1.8*10^-6 kg

a= 0.32 m/s²

Learn more about electric force at: brainly.com/question/25923373

#SPJ4

The value of escape velocity will be 2.38 Km/s

The minimal speed necessary for an object to liberate itself from the gravitational attraction imposed by a big object is defined as escape speed, also known as escape velocity.

Escape velocity is the minimal velocity necessary to overcome a big body's gravitational potential and escape to infinity.

The velocity at which an item circles around a huge body is referred to as orbital velocity.

The escape speed from the moon can be calculated using the formula:

[tex]v_{escape = \sqrt{(2GM/r)[/tex]

Where G is the gravitational constant (6.67x10^-11 N.m^2/kg^2),

M is the mass of the moon (7.36x10^22 kg), and

r is the radius of the moon (1740 km or 1.74x10^6 m).

Plugging in the values, we get:

[tex]v_{escape = \sqrt{(2 \times 6.67 \times 10^{-11} \times 7.36 \times 10^22 / 1.74 \times 10^6)[/tex]

= 2.38 km/s

For more questions on escape speed

https://brainly.com/question/29503674

#SPJ4

32.8N/m is the spring constant of the spring.

How does simple harmonic motion work?

Simple harmonic motion is described as the periodic motion of a point along a straight line with an acceleration that is always toward a fixed point in that line and a distance from that point that is proportional to that acceleration.

When the restoring force is inversely proportional to the displacement, the oscillations are the simplest. Recall that the equation F = kx from Hooke's law represents this circumstance. Thus, simple harmonic motion, the most basic type of oscillation, is described by and subject to Hooke's law.

We know that:

T=2π√m/k

k=4π^2×m/T^2

m = 0.42kg

T = 0.71s

k= 4*3.14*3.14*0.42/ 0.71*0.71

k = 32.8N/m

To learn more about oscillations use link below:

https://brainly.com/question/22499336

#SPJ4

The height h of mercury in the right side of the U-tube is 4.37 cm.

The Bernoulli's principle of fluid dynamic states that as a fluid's static pressure or potential energy falls, so too does its speed.

Given,

Rate if volume flow Q = 1200 cm³/s

The broader end diameter D1 = 2.0 cm

The narrower end diameter D2 = 0.4 cm

By using bernoulli's theorem,

1/2pv1² + P1 = 1/2pv2² + P2

P1 - P2 = 1/2pv1² - 1/2pv2²

By using continuity equation,

Q = π(D1²/2)²v1 = π(D2²/2)²v2 = 1200 cm³/s

v2 = 4 × 1200 cm³/s / π × (0.4)² = 9550 cm/s = 95.5 m/s

v1 = 4 × 1200 cm³/s / π × (2)² = 382 cm/s = 3.82 m/s

P1 - P2 = 1/2 p(v2² - v1²)

P1 - P2 = 1/2 × 1.28 kg/m³ × ( (95.5m/s)² - (3.82m/s)² )

P1 - P2 = 5827.6 N/m²

then,

pgh = 5827.6 N/m²

h = 5827.6 N/m² / pg

h = 5827.6 N/m² / 13600 kg/m³ × 9.8 m/s² = 0.0437 m

h = 4.37 cm.

To learn more about bernoulli's principle visit,

https://brainly.com/question/13098748

#SPJ4

Q. Air flows through the tube shown in figure below at a rate of 1200 cm³/s. Assume that air is an ideal fluid. What is the height h of mercury in the right side of the U-tube?

The same as the voltage across the 20-watt light, which is 30 volts.

When two or more electrical components are connected in parallel, they are connected to the same voltage source and share the same potential difference. In this case, the 10-watt cabin entry light and the 20-watt dome light are connected in parallel to a 30-volt source.

Since they are connected to the same voltage source, the voltage across both components will be the same, which is 30 volts. This is because the potential difference across each component is determined by the voltage of the source, and not by the power or current that the component requires.

The power and current of each component will be determined by the component's resistance and the voltage across it. However, since the voltage across both components is the same, their power and current will be determined by their own individual resistances.

So even though the dome light requires more power than the cabin entry light, they will both receive the same voltage and the same potential difference.

Learn more about the potential difference here:

https://brainly.com/question/24142403

#SPJ4

The solution for 2 periods are x ( t) = 1 cos 2t + √5₂ Sin 2t

x ( t ) = cos 2 t + ( .1 ) 8 sin 2 t. and we can plot a graph using them

Given mx + kx = 0

x + k/m x = 0

Wn = √K/m = 2

(Dᵃ + k/m) = 0

0 =  ± i (2)

x (t) = c1 cos √k/m t + c2 sin √k/m t

x (1) = c1 cos 2t + c2 sin2t

x(0) = 1 mm

x (0) = c1 = 1 mm

x ( t ) = -2 c2 sin2t +2 c2 cos 2t

x ( 0 ) = v0 =√ 5 = 0 + 2c2

c2 = (√5₂

x ( t) = 1 cos 2t + √5₂ Sin 2t

x ( t ) = cos 2 t + ( .1 ) 8 sin 2 t

using the above two equations we can plot a graph for the two periods.

To learn more about graph click here:

https://brainly.com/question/24861666

#SPJ4

The center of gravity of a three-dimensional rigid object is an important concept in physics and engineering for several reasons like stability, Dynamics, Design, Lifting and handling, etc.

Stability: The CoG of an object determines its stability. An object is considered stable if its CoG is located above its support base. If the CoG is not located above the support base, the object is considered unstable.

Dynamics: The CoG is used in the study of the dynamics of objects in motion. The CoG of an object is used to determine the forces and their reactions to those forces.

Design: in the design of objects, especially in engineering the location of the CoG can affect the stability, balance, and efficiency of an object, and it is often optimized during the design process.

Lifting and Handling: The CoG is used to determine the best way to lift and handle an object. If the CoG is known, it is easier to determine the most efficient and safe way to lift and move the object, reducing the risk of injury or damage.

To know more about center of gravity, here

https://brainly.com/question/15577146

#SPJ4

Answer:

balence

Explanation:

A balance scale would be the most accurate tool for a parent to use when trying to compare the masses of their kids' backpacks.

The best tool for comparing the masses of the backpacks would be a balance scale. A balance scale allows for precise comparison of items' weight or mass. In order to use the tool, the parent would first place one backpack on one side of the balance scale and the second backpack on the other side. The balance scale will tip towards the side of the heavier backpack, allowing the parent to determine which one has a larger mass. For a more quantitative measurement, weights can be added to the lighter side until the scale balances again. The total mass of the weights then corresponds to the mass of the heavier backpack.

https://brainly.com/question/33723649

#SPJ2

A region has a uniform electric field of 200,000 N/C directed to the Southwest. The electric force on this electron would point southwest (opposite to the direction of the electric field.)

Imagine yourself in an electric field. This field would exert an electric force on a positive point charge placed there. By definition, the field's direction at that location corresponds to the force that it applies to the positive point charge there in terms of electric field.

It should be obvious that the electric field in this area in this query points northeast. A positive point charge would therefore experience an electric force in the same direction—to the northeast—if it were placed in this area.

Negative charge characterizes electrons. An electron would experience electric force in the opposite direction from a positive point charge positioned in the same location. The positive point charge in this area has an electric force that points northeast (same as the direction of the electric field). Southwest is the polar opposite of northeast. Therefore, the direction of the electric field acting on an electron in this location would be southwest

Learn more about Electric field here

https://brainly.com/question/28022029

#SPJ4

The peak current in a 5.6 k resistor connected to a 120 v rms ac source   Is 0.03 Amp.

The peak current is the maximum amount of current which output is capable of sourcing for brief periods of time. When a power supply or an electrical device is first turned on, high initial current flows into the load, starting at zero and rising until it reaches a peak value, known as the peak current.

Vrms = 120v , R = 5600 ohm

Peak current = Ip

                      = peak voltage /resistance = Vp/R

Also Vp = Vrma × √2

=) Ip = Vrms ×√2 /R

       = 120√2/5600 = 0.0303 A

=) Ip = 0.03A

Learn more about peak current here :

https://brainly.com/question/28331261

#SPJ4

The distance traveled is not equal to the magnitude of displacement in the following examples: Rabbit returns home after going to eat dandelions 5 m away.

To learn more about the magnitude of displacement refer to:

https://brainly.com/question/19104773

#SPJ4

The average speed of the car is 50 km/h and in miles per hour it is 31.0686 miles.

Average speed can be defined as the total distance travelled by an object in a particular time period. This is a scalar quantity. The SI unit of average speed is meter per second.

A. Distance travelled in half an hour = 25km

Therefore, the distance covered in an hour = 25 × 2 = 50km

The speed of the car will be 50km/hr

B. The in average speed miler per hour will be:

1km = 0.621371miles

50km = 31.0686 miles

The speed will be 31068 miles per hour.

C. Speed of cheetah = 25m/s

If, the time is 5 seconds then the distance covered by the cheetah with this speed will be:

Speed = Distance/ Time
25 = D/ 5

Distance = 25 × 5

Distance = 125 meters

D. Distance travelled in 1 minute = 60 seconds will be:

Speed = Distance/ Time

25 = D/ 60

Distance = 25 × 60

Distance = 1500 meters

Learn more about Speed here:

https://brainly.com/question/28224010

#SPJ1

The answer to the multiple questions asked on friction, Humidity,  triboelectric effect and static electricity is given below.

14. A-tape (or B-tape) is attracted to a neutral object because the tape acquires a static charge through friction, and like charges repel each other while opposite charges attract. When the charged tape comes near a neutral object, the neutral object acquires an electric charge of the opposite sign, causing an attraction between the charged tape and the neutral object.

15. Humid air makes it difficult to perform experiments with static electricity because the humidity in the air provides a path for the static charge to flow to the ground, thus reducing the charge on the object. This is because water is a good conductor of electricity, allowing the static charge to dissipate more quickly than in dry air.

16. When you rub your fingers on the non-sticky side of A-tape, you transfer some electrons from your fingers to the tape, effectively neutralizing its charge. The triboelectric effect, which is the transfer of electrons from one material to another through friction, can result in a buildup of static charge on the tape. By rubbing your fingers on the tape, you equalize the distribution of electrons between the tape and your fingers, neutralizing the charge on the tape.

17. Clothes taken out of the dryer tend to have a lot of static electricity because of the triboelectric effect. As the clothes rub against each other and the dryer drum during the tumbling and spinning action, they transfer electrons, resulting in a buildup of static charge. Dryer sheets work to eliminate this static charge by releasing positively charged ions into the dryer that neutralize the static charge on the clothes. The positively charged ions are attracted to the negatively charged clothes, effectively reducing the static charge and making the clothes less likely to cling to each other.

Learn more about friction here:

https://brainly.com/question/13000653

#SPJ4

The basketball player must be moving at approximately 10.5 m/s to jump 1.9 m.

To calculate the speed the player must be moving at to jump 1.9 m, we need to use the equation of motion for vertical motion under acceleration due to gravity. This equation is:

v^2 = u^2 + 2as

where:

v = final velocity (speed)

u = initial velocity (speed)

a = acceleration due to gravity (9.8 m/s^2)

s = vertical distance (1.9 m)

Since the player is jumping vertically from rest (u = 0), the equation becomes:

v^2 = 2as

Substituting in the values for a and s:

v^2 = 2 * 9.8 * 1.9

v^2 = 37.24

Taking the square root of both sides:

v = sqrt(37.24)

v = approximately 6.1 m/s

So, the player must be moving at approximately 6.1 m/s the instant her foot leaves the ground to jump 1.9 m.

To know more about speed calculation here:

https://brainly.com/question/29775794#

#SPJ11

The acceleration due to gravity on that planet is 6.13 m/s², if the height of drop of wrench is 1.52 m and time is 0.705 seconds.

Initial velocity of the wrench, u = 0   [initially at rest]

Height travelled by the wrench, h = 1.52 m

Time taken to travel through 1.52 m height, t = 0.705 sec

Let the acceleration due to gravity at that planet is g.

By the second equation of motion,

h = ut + 0.5gt²

1.52 = 0 × t + 0.5 × g × 0.705²

1.52 = 0.248g

g = 1.52/0.248

g = 6.13 m/s²

To know more about acceleration, here

https://brainly.com/question/12550364

#SPJ4

The correct answer is 4 numbers of angles to measure to map out the position of a sky object at any particular time.

What is Degrees (°) are the units used by astronomers?

Degrees (°) are the units used by astronomers to measure the "angular distance" between celestial objects. There are 90 degrees between any point on the horizon and the highest top of the sky because a circle has 360 degrees.

So we can conclude there are 4 number of angles as 90 arc minute in sky object.

To learn more about angles of sky object from the given link

https://brainly.com/question/4921242

#SPJ4

If the temperature rises to 28°c, the submerged volume fraction of the cube will increase by 0.2%.

Due to a temperature increase is defined by the following expression:

at 20∘c and then its temperature is increased by 100∘c

When the iron cube if partly immersed in mercury, the buoyant force that is acting on it will be

FB=ρVg where V is the volume of the iron cube immersed in the liquid.

Since we have a constant mass of the iron cube, from the relation of density with mass and volume for the iron cube

ρi=miVi

since the density of the iron block will decrease, to produce the same amount of buoyant force (FB=ρVg), the volume of the iron block immersed in the liquid will have to increase for the cube to not sink in the mercury.

Part (a)

If the temperature rises to 28°c, then the cube will float lower since the submerged fraction is higher (0.580), and before it was 0.578.

Part (b)

If the temperature rises to 28°c, the submerged volume fraction of the cube will increase by 0.2%. In effect, when the temperature was 0°c the submerged fraction was 57.8%, then the temperature increases to 28°c and the submerged fraction is now 58.0%.

Learn more about volume change here :

https://brainly.com/question/14280103

#SPJ4

The spectral type of a star is the characteristic that most directly influences its color.

A star's spectral type determines its color uniquely. A star's color is intimately correlated with its spectral class. also The hue of light emitted by a star depends on its surface temperature. Yellow stars are hotter than red stars, and yellow stars are hotter yet than blue stars. A red dwarf is the most common type of star. Spectral classes are divided into seven categories. These seven spectral classes are denoted by the letters O, B, A, F, G, K, and M, ranging from hottest to coolest. Recently, three other classes—L, T, and Y—have been introduced by astronomers for even cooler objects.

Learn more about Spectral Type

brainly.com/question/28216076

#SPJ4