does work done by the electric force depends on the path taken.

Answer:

Explanation:

We shall use Ampere's circuital law to find magnetic field at required point.

The point is outside the circumference of two given wires so whole current will be accounted for .

Ampere's circuital law

B = ∫ Bdl = μ₀ I

line integral will be over circular path of radius r = 41 cm .

Total current  I  = 5A -3A = 2A .

∫ Bdl = μ₀ I

2π r B = μ₀ I

2π x .41  B = 4π x 10⁻⁷ x 2

B = 2 x 10⁻⁷ x 2 / .41

= 9.75 x 10⁻⁷ T . It will be along - ve Y - direction.

Answer:

For eintein's frame of reference, both beam travel at the same speed.

For my own frame of reference, both beams travel at the same speed.

Explanation:

According to special relativity, the speed of light is the same in all direction on all reference frame. If not for this law we will assume the from beam will have a relative speed that will be the speed of light plus the speed of the fright car. This is not so and it violates the speed limit of light which according to the first law is the highest speed possible and nothing can go beyond that.

Answer:

340 W

Explanation:

Power = change in energy / change in time

P = ΔKE / Δt

P = ½ mv² / Δt

P = ½ (90 kg) (15 m/s)² / (30 s)

P = 337.5 W

Rounded to 2 significant figures, the power is 340 W.

Answer:

The extent of greenhouse effect on mars is [tex]G_m = 87 K[/tex]  

Explanation:

From the question we are told that

     The albedo value of Mars is  [tex]A_1 = 0.15[/tex]

      The albedo value of Mars is  [tex]A_2 = 0.15[/tex]

       The surface temperature of Mars is  [tex]T_1 = 220 K[/tex]

        The surface temperature of Venus is  [tex]T_2 = 700 K[/tex]

          The distance of Mars from the sun is [tex]d_m = 2.28*10^8 \ km = 2.28*10^8* 1000 = 2.28*10^{11} \ m[/tex]

          The distance of Venus from sun is  [tex]d_v = 1.08 *10^{8} \ km = 1.08 *10^{8} * 1000 = 1.08 *10^{11} \ m[/tex]

       The radius of the sun is [tex]R = 7*10^{8} \ m[/tex]

        The energy flux is   [tex]E = 6.28 * 10^{7} W/m^2[/tex]

The solar constant for Mars is mathematically represented as

          [tex]T = [\frac{E R^2 (1- A_1)}{\sigma d_m} ][/tex]

Where [tex]\sigma[/tex] is the Stefan's constant with a value  [tex]\sigma = 5.6*10^{-8} \ Wm^{-2} K^{-4}[/tex]

So substituting values

         [tex]T = \frac{6.28 *10^{7} * (7*10^8)^2 * (1-0.15)}{(5.67 *10^{-8}) * (2.28 *10^{11})^2)}[/tex]

          [tex]T = 307K[/tex]

So the greenhouse effect on Mars is  

           [tex]G_m = T - T_1[/tex]

           [tex]G_m = 307 - 220[/tex]

          [tex]G_m = 87 K[/tex]

Answer:

The initial momentum of the ball is 8 kg-m/s.

Explanation:

Given that,

Mass of the ball is 4 kg

Initial speed of the ball is 2 m/s

Force applied to the ball is 5 N for 3 seconds

It is required to find the initial momentum of the ball. Initial momentum means that the product of mass and initial velocity of the ball. It is given as :

[tex]p_i=mu\\\\p_i=4\ kg\times 2\ m/s\\\\p_i=8\ kg-m/s[/tex]

So, the initial momentum of the ball is 8 kg-m/s.

Answer:

To create a second harmonic the rope must vibrate at the frequency of 3 Hz

Explanation:

First we find the fundamental frequency of the rope. The fundamental frequency is the frequency of the rope when it vibrates in only 1 loop. Therefore,

f₁ = v/2L

where,

v = speed of wave = 36 m/s

L = Length of rope = 12 m

f₁ = fundamental frequency

Therefore,

f₁ = (36 m/s)/2(12 m)

f₁ = 1.5 Hz

Now the frequency of nth harmonic is given in general, as:

fn = nf₁

where,

fn = frequency of nth harmonic

n = No. of Harmonic = 2

f₁ = fundamental frequency = 1.5 Hz

Therefore,

f₂ = (2)(1.5 Hz)

f₂ = 3 Hz

Answer:

t = 0.029 s

Explanation:

We have,

Speed of sound is 343 m/s.

Dezeirey is positioned 5 m behind her.

It is required to find the time taken for the echo from the wall to reach her. The total distance covered by the echo when it reaches her is 2d or 10 m.

Time taken,

[tex]t=\dfrac{d}{v}\\\\t=\dfrac{10\ m}{343\ m/s}\\\\t=0.029\ s[/tex]

So, it will take 0.029 seconds for the echo from the wall to reach her.

Answer:

The length of cable is 12.5 m

Explanation:

Since, the wrecking ball completes 1 oscillation, in the same time, as it takes for the rock to complete 5 oscillations.

Therefore,

Time Period of Wrecking Ball = 5 (Time Period of Rock)

Since,

Time Period of  Pendulum = 2π√(L/g)

Therefore,

2π√(L₁/g) = 5[2π√(L₂/g)]

√L₁ = 5√L₂

Squaring on both sides:

L₁ = 25 L₂

where,

L₁ = Length of Cable = ?

L₂ = Length of string = 0.5 m

Therefore,

L₁ = 25 (0.5 m)

L₁ = 12.5 m

Answer:

the volocity is 50

Explanation:

Answer:

Flying cars.

Explanation:

Answer:

Force applied to stop the car = 1,250 N

Explanation:

Given:

Mass of car (M) = 1,000 kg

Initial velocity (U) = 20 m/s

Final velocity (V) = 0 m/s

Distance (S) = 160 m

Find:

Force applied to stop the car.

Computation:

[tex]v^2 = u^2 + 2as\\\\0^2=20^2+2(a)(160)\\\\0=400+320(a)\\\\Acceleration = a = -1.25m/s^2\\\\Force = ma \\\\Force= 1,000(1.25)\\\\Force = 1,250 N[/tex]

Force applied to stop the car = 1,250 N

Answer: An increase in carbon dioxide will occur in the atmosphere because there are less trees to use the gas in the process of photosynthesis.

Explanation: Photosynthesis can be simply defined as a process where green plants uses minerals from the soil, water and carbon dioxide to produce their own food (energy-rich organic compound/starch) while oxygen is released into the environment.

On the other hand, Human beings and other animals inhales the oxygen released into the environment by green plants and breath out carbon dioxide.

Deforestation is the permanent removal trees either for commercial or household use or in some cases, to make room or space for other activities or development.

Now when these trees (green plants) are permanently cut down without replacement, humans and other animals continuously exhale carbon dioxide and there will be little or no green plants (trees) available to convert this carbon dioxide into oxygen.

Hence, there will be an increased amount of carbon dioxide in the atmosphere as their are little or no tress to use the gas (carbon dioxide) in the process of photosynthesis.

Answer:

A) equal to the battery's terminal voltage.

Explanation:

When the capacitor is fully charged after long hours of charging , its  potential becomes equal to the emf of the battery and its polarity is opposite to that of battery . Hence net emf becomes equal . The capacitor itself becomes a battery which is connected in the circuit with opposite polarity . This results in the net emf and  current becoming zero . There is no charging current when the capacitor is fully charged .

Answer:

Since gravitational force is inversely proportional to the square of the separation distance between the two interacting objects, more separation distance will result in weaker gravitational forces. So as two objects are separated from each other, the force of gravitational attraction between them also decreases.

answer: It is inversely proportional to the square of the distance.

Explanation:

for the team

Answer:

Explanation:

According to first law of thermodynamics :

Q = ΔE + W

Q is heat added , ΔE is increase in the internal energy of the system and W is work done by the system .

Here Q = 36 KJ

ΔE = 14 kJ

Putting the values in the equation

36 = 14 + W

W = 36 - 14

= 22 kJ .

Work done by gas or system = 22 kJ.

Answer:

Explanation:

moment of inertia of each blade which is similar to rod rotating about its one end

= 1/3 ml²

moment of inertia of 3 blades = ml²

= 5500 x 46²

I = 11638 x 10³ kg m²

angular velocity = 2πn where n is rotation per second

n = 11 / 60

angular velocity = 2π x 11/60

= 1.1513 rad /s

angular momentum

= moment of inertia x angular velocity

=  11638 x 10³ x 1.1513

= 13399 x 10³ kg m² per second.

Answer:

The temperature is [tex]T = -106 ^oC[/tex]

Explanation:

From the question we are told that

   The temperature is [tex]T_1 = T_t= T_a=15^oC[/tex]

   The  diameter is  [tex]d_1 = 0.5001 cm[/tex]

    The diameter of the hole [tex]d_2 = 0.500 \ cm[/tex]

    The coefficient of linear expansion for aluminum is [tex]\alpha _1 = 25 *10^{-6} \ ^oC^{-1}[/tex]

    The coefficient of linear expansion for  titanium is [tex]\alpha _2 = 8.5 *10^{-6} \ ^o C^{-1}[/tex]

According to the law of linear expansion

     [tex]d = d_o (1 + \alpha \Delta T )[/tex]

Where [tex]d_o[/tex] represents the original diameter

  So for aluminum

          [tex]d_a = d_1 (1 + \alpha_1 (T- T_a) )[/tex]

Where [tex]d_a[/tex] is the new diameter of aluminum

          [tex]T_a[/tex] is the new temperature of the aluminum

So for titanium

      [tex]d_t = d_2 (1 + \alpha_1 (T- T_t) )[/tex]

Where [tex]d_t[/tex] is the new diameter of  titanium

          [tex]T_t[/tex] is the new temperature of the aluminum

So for the aluminum rivets to fit into the holes

     [tex]d_a = d_t[/tex]

=>  [tex]d_1 (1 + \alpha_1 (T- T_a) ) = d_2 (1 + \alpha_2 (T- T_t) )[/tex]

       Making T the subject of the formula

     [tex]T = \frac{(d_1 - d_2 ) + (d_2 *\alpha_2 T_t) - d_1 \alpha_1 * T_a }{d_2 \alpha_2 - d_1 \alpha_1 }[/tex]

    Substituting values

     [tex]T = \frac{(0.501 - 0.500 ) + (0.500 *(8.5*10^{-6}) * 15) - 0.500* (25*10^{-6}) * 15 }{0.500 * (8.5 *10^{-6}) - 0.501 * (25 *10^{-6}) }[/tex]

    [tex]T = -106 ^oC[/tex]

Answer:

b) 20 kJ

Explanation:

Efficiency of carnot engine = (T₁ - T₂ ) / T₁  Where T₁ is temperature of hot source  and T₂ is temperature of sink .

T₁ = 270 + 273 = 543K

T₂ = 50 + 273 = 323 K

Putting the given values of temperatures

efficiency = (543 - 323) / 543

= .405

heat input = 50 KJ

efficiency = output work / input heat energy

.405 = output work / 50

output work = 20.25 KJ.

= 20 KJ .

Answer:

20cal/s

Explanation:

Question:

There are two questions. The first one has been answered:

From the formular, Power = Q/t = (kA∆T)/l

the amount heat depends on the duration of time interval, length of the iron rod, the thermal conductivity of iron and the temperature difference between the ends of the rod.

The amount of heat that flows through the rod by conduction during a given time interval does not depend upon the mass of the iron rod (D).

Second question:

The ends of a cylindrical steel rod are maintained at two different temperatures. The rod conducts heat from one end to the other at a rate of 10 cal/s. At what rate would a steel rod twice as long and twice the diameter conduct heat between the same two temperatures?

Solution:

Power = 10cal/s

Power = energy per unit time = Q/t

Where Q = energy

Power = (kA∆T)/l

k = thermal conductivity of iron

A = area

Area = πr^2

r = radius

Diameter = d = 2r

r = d/2

Area = (πd^2)/4

Length = l

∆T = change in temperature

10 = (kA∆T)/l

For a steel rod with length doubled and diameter doubled:

Let Length (L) = 2l

Diameter (D)= 2d

Area = π [(2d)^2]/4 = (π4d^2)/4

Area = 4(πd^2)/4

Using the formula Power = (kA∆T)/l, insert the new values for A and l

Power = [k × 4(πd^2)/4 × ∆T]/2l

Power = [4k((πd^2)/4) ∆T]/2l

Power = [(4/2)×k((πd^2)/4) ∆T]/l

Power = [2k(A) ×∆T]/l = 2(kA∆T)/l

Power of a steel that has its length doubled and diameter doubled = 2(kA∆T)/l

Recall initial Power = (kA∆T)/l = 10cal/s

And ∆T is the same

2[(kA∆T)/l] = 2 × 10

Power of a steel that has its length doubled and diameter doubled = 20cal/s

Answer:

The displacement of particles is perpendicular to the direction of wave motion.

Answer:

The work will be "600 kJ/kg".

Explanation:

(1-a) ⇒ Constant Pressure

(a-2) ⇒ Constant Volume

The given values are:

In state 1,

Pressure, P₁ = 200 kPa

Volume, V₁ = 2m³

In state 2,

Pressure, P₂ = 1000 kPa

Volume, V₁ = 5m³

Now,

In process (1-a), work will be:

⇒ W₁₋ₐ = P₁(Vₐ - V₁)

On putting the values, we get

⇒ W₁₋ₐ = 200(5-2)

⇒         = 200(3)

⇒         = 600 kJ/kg

In process (a-2), work will be:

⇒ Wₐ₋₂ = 0

∴ (The change in the volume will be zero.)

So,

⇒ Total work = (W₁₋ₐ) + (Wₐ₋₂)

⇒                    = 600 + 0

⇒                    = 600 kJ/kg

Answer:

1.04 x 107 J.

Explanation:

We can use the following method to do the calculation

Total energy given to water to convert intosteam

dQ = m* l

dQ = 5.00* 2.26 * 106

= 1.13* 107 J

Work done at constantpressure dW = P* dV

Initialvolume V1 = 5.00kg / 958

= 5.22* 10-3 m3

Finalvolume = 8.50 m3

=> dW = 1.01* 105 * ( 8.50 - 5.22 * 10-3)

= 8.58* 105 J

First law of thermodynamicsis dQ = ΔU + dW

Change in internalenergy ΔU = 1.13* 107 - 8.58 *105

= 1.04 x 107 J as our answer

Answer:

a) [tex]\omega = 13.2t^2\frac{rad}{s^3}+2.80t\frac{rad}{s^2}[/tex]

b) [tex]\alpha=26.4t\frac{rad}{s^3}+2.80\frac{rad}{s^2}[/tex]

Explanation:

You have that the angular displacement is given by:

[tex]\theta=4.40t^3\frac{rad}{s^3}+1.40t^2\frac{rad}{s^2}[/tex]

a) the angular velocity is given by the derivative in time, of the angular displacement, that is:

[tex]\omega=\frac{d\theta}{dt}=\frac{d}{dt}[4.40 t^3 rad/s^3 + 1.40 t^2 rad/s^2]\\\\\omega=\frac{d\theta}{dt}=13.2t^2\frac{rad}{s^3}+2.80t\frac{rad}{s^2}[/tex]

b) the angular acceleration is the derivative, in time, of the angular velocity:

[tex]\alpha=\frac{d\omega}{dt}=\frac{d}{dt}[13.2t^2\frac{rad}{s^3}+2.80t\frac{rad}{s^2}]\\\\\alpha=26.4t\frac{rad}{s^3}+2.80\frac{rad}{s^2}[/tex]

Answer:

the answers the correct one is cη

Explanation:

In this simple pendulum experiment the student observes a significant change in time between each period. This occurs since an approximation used is that the sine of the angle is small, so

              sin θ = θ

with this approach the equation will be surveyed

     d² θ / dt² = - g / L sin θ

It is reduced to

      d² θ / dt² = - g / L θ

in which the time for each oscillation is constant, for this approximation the angle must be less than 10º so that the difference between the sine and the angles is less than 1%

The angle is related to the height of the pendulum

         sin θ = h / L

         h = L sin θ.

Therefore the student must be careful that the height is small.

When reviewing the answers the correct one is cη

Considering the approximation of simple harmonic motion, the correct option is:

(c) Make sure that the difference in height between the pendulum's release position and rest position is not too large.

According to Newton's second law in case of rotational motion, we have;

[tex]\tau = I \alpha[/tex]

Applying this, in the case of a simple pendulum, we get;

[tex]-mg\,sin\,\theta =mL^2 \,\frac{d^2 \theta}{dt^2}[/tex]

On, rearranging the above equation, we get;

[tex]mL^2 \,\frac{d^2 \theta}{dt^2} + mg\,sin\,\theta=0\\\\\implies \frac{d^2 \theta}{dt^2} +\frac{g}{L} sin \,\theta=0[/tex]

Now, if angular displacement is very small, i.e.; the bob of the pendulum is only raised slightly.

Then, [tex]sin\, \theta \approx \theta[/tex]

[tex]\implies \frac{d^2 \theta}{dt^2} +\frac{g}{L} \,\theta=0[/tex]

This is now in the form of the equation of a simple harmonic motion.

[tex]\frac{d^2 \theta}{dt^2} +\omega^2 \,\theta=0[/tex]

Comparing both these equations, we can say that;

[tex]\omega = \sqrt{\frac{g}{L}}[/tex]

[tex]T=2\pi\sqrt{\frac{L}{g}}[/tex]

This relation for the time period can only be obtained if the angular displacement is very less.

So, the correct option is;

Option (c): Make sure that the difference in height between the pendulum's release position and rest position is not too large.

Learn more about simple harmonic motion here:

https://brainly.com/question/26114128

Answer:

Explanation:

A fan pushes hot air out of a vent and into a room. The hot air displaces cold air in the room, causing the cold air to move closer to the floor.

The hot air displacing the cold air is an example of  transfer by

Answer:

-7.23 rad/s

Explanation:

Given that

Mass of the cockroach, m = 0.157 kg

Radius of the disk, r = 14.9 cm = 0.149 m

Rotational Inertia, I = 5.92*10^-3 kgm²

Speed of the cockroach, v = 2.92 m/s

Angular velocity of the rim, w = 3.89 rad/s

The initial angular momentum of rim is

Iw = 5.92*10^-3 * 3.89

Iw = 2.3*10^-2 kgm²/s

The initial angular momentum of cockroach about the axle of the disk is

L = -mvr

L = -0.157 * 2.92 * 0.149

L = -0.068 kgm²/s

This means that we can get the initial angular momentum of the system by summing both together

2.3*10^-2 + -0.068

L' = -0.045 kgm²/s

After the cockroach stops, the total inertia of the spinning disk is

I(f) = I + mr²

I(f) = 5.92*10^-3 + 0.157 * 0.149²

I(f) = 5.92*10^-3 + 3.49*10^-3

I(f) = 9.41*10^-3 kgm²

Final angular momentum of the disk is

L'' = I(f).w(f)

L''= 9.41*10^-3w(f)

Using the conservation of total angular momentum, we have

-0.068 = 9.41*10^-3w(f) + 0

w(f) = -0.068 / 9.41*10^-3

w(f) = -7.23 rad/s

Therefore, the speed of the lazy Susan after the cockroach stops is -7.23 and is directed in the opposite direction of the initial lazy Susan angular speed

b)

The mechanical energy of the cockroach is not converted as it stops

Answer:

Time of flight=3.5 seconds

Speed at maximum height is 0

Explanation:

Φ=60°

initial velocity=u=20m/s

Acceleration due to gravity=g=9.8 m/s^2

Total time of flight=T

Final speed=v

question 1:

T=(2 x u x sinΦ)/g

T=(2 x 20 x sin60)/9.8

T=(2 x 20 x 0.8660)/9.8

T=34.64/9.8

T=3.5 seconds

Question 2

Speed at maximum height is 0

OB

mmnjnjlkdhfutydjfyiudtkcgvyftdcgvjyiluftgyiuyu  ( had to do that cuz it wouldn't let through)

Answer:

The third image

Explanation:

The one with the thumb pointing to the right

Answer:

3, correct on Edge 2020