Physics College

## Answers

**Answer 1**

**Answer:**

Choice **a**. [tex]70\; \rm N[/tex], assuming that the skating rink is level.

**Explanation:**

Net force in the horizontal direction

There are two horizontal forces acting on the boy:

The pull of his friend, andFrictions.

The boy should be moving in the direction of the pull of his friend. The frictions on this boy should oppose that motion. Therefore, the frictions on the boy would be in the opposite direction of the pull of his friend.

The net force in the horizontal direction should then be the difference between the pull of the friend, and the friction on this boy.

[tex]\text{Net force, horizontal} = 75\; \rm N - 5\; \rm N = 70\; \rm N[/tex].

Net force in the vertical direction

The net force on this boy should be zero in the vertical direction. Consider Newton's Second Law of motion. The net force on an object is proportional to its acceleration. In this question, the net force on this boy in the vertical direction should be proportional to the vertical acceleration of this boy.

However, because (by assumption) the ice rink is level, the boy has no motion in the vertical direction. His vertical acceleration will be zero. As a result, the net force on him should also be zero in the vertical direction.

Net force

Therefore, the (combined) net force on this boy would be:

[tex]\sqrt{(70\; \rm N)^2 + (0\; \rm N)^2} = 70\; \rm N[/tex].

**Answer 2**

The answer is a hope it helps

## Related Questions

A kayaker moves 26 meters southward, then 18 meters

northward, and finally 12 meters southward.

For this motion, what is the distance moved?

What is the magnitude and direction of the displacement?

### Answers

Total distance: 56 meters. Magnitude and direction of displacement: 20 meters South.

Explanation:

The term distance refers to space between one point and other, or the total space a body or object covered while moving. In the case presented, this can be calculated by adding the partial distances given. This means the total distance is 56 meters as 26 meters + 18 meters + 12 meters = 56 meters.

On the other hand, displacement considers the distance from the initial position to the final position, and the direction of movement. This means partial distances should not be added but each movement should be considered according to the direction. The process is shown below:

-The first movement was 26 meters southward; this means by the end of this movement the distance between the initial position was 26 meters south.

- The second movement was 18 northward; this means the kayaker moved 18 meters towards the position. This changes the displacement to 8 meters South as 26 meters south - 18 meters north = 8 meters to the South.

-The last movement was 12 meters sound; this means the kayaker increased the distance from the original position 8 meters to the South + 12 meters to the South = 20 meters South (total displacement.)

A yellow train of mass 100 kg is moving at 8 m/s toward an orange train of mass 200 kg traveling in the opposite direction on the same track at a speed of 1 m/s. What is the initial momentum of the orange train?.......... A. 200 kgm/s B. -200 kgm/s C. 100 kgm/s D. 80 kgm/s

### Answers

**Answer:****The**** ****answer**** ****is**** ****option**** ****A****.**

Momentum=mass×velocity.

Orange train=mass is 200 and velocity is 1.

which is 200×1=200kgm/s.

The** initial momentum** of the **orange train** is** 200 kgm/s.**

What is momentum?**Momentum** is the product of** mass** and **velocity** of any object.Momentum is denoted by** P.**Momentum** P = mv** , where** m = mass** and** v = velocity.**Momentum is a** vector quantity.**

How to calculate momentum of the orange train?

**The orange train** is having **mass **of **200 kg** and it is travelling with** speed **of **1 m/s. **

So, the orange trains momentum will be ,

** P = mv**

∴ P = 200 x 1

** ∴ P = 200 kgm/s**

Therefore, the** initial momentum **of **the orange train** is **200kgm/s.**

Learn more about **momentum** here -

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How fast must a meter stick be moving if its length is observed to shrink to 0.57 m?

### Answers

Answer:

0.8216c

Explanation:

Using the relationship

L' = L√(1 - v²/c²)

where

L = original length,

L' = observed length,

v = velocity,

c =speed.

L'/L = 0.57

Then

0.57 = √(1 - v²/c²)

1 - v²/c² = 0.57² = 0.3249

v²/c² = 1 - 0.3249 = 0.6751

v² = 0.6751c²

v = c√0.6751 = 0.8216c

Explanation:

Suppose you spray your sister with water from a garden hose. The water is supplied to the hose at a rate of 0.625×10−3 m3/s and the diameter of the nozzle you hold is 5.19×10−3 m. At what speed v does the water exit the nozzle?

### Answers

**Answer:**

**0.153 m/s**

**Explanation:**

The flowrate Q = 0.625 x 10-3 m^3-/s

The diameter of the nozzle d = 5.19 x 10^-3 m

the velocity V = ?

The cross-sectional area of the flow A = [tex]\pi d^{2}/4[/tex]

==> (3.142 x 5.19 x 10^-3)/4 = 4.077 x 10^-3 m^2

From the continuity equation,

Q = AV

V = Q/A = (0.625 x 10-3)/(4.077 x 10^-3) = **0.153 m/s**

Two gratings A and B have slit separations dA and dB, respectively. They are used with the same light and the same observation screen. When grating A is replaced with grating B, it is observed that the first-order maximum of A is exactly replaced by the second-order maximum of B. (a) Determine the ratio dB/dA (No units) of the spacings between the slits of the gratings. Then find the next two principla maxima of grating A and the principal maxima of B that exactly replace them when the gratings are switched [(b) and (c) for the first pair, (d) and (e) for the second pair]. Identify these maxima by their order numbers (No units), listing the maxima for grating B first.

### Answers

**Answer:**

a) dB / dA = 2,

b) Network B Network A

2 1

4 2

6 3

**Explanation:**

a) The expression for grating diffraction is

d sin θ = m λ

where d the distance between two slits, λ the wavelength and m an integer that represents the diffraction range

In this exercise we are told that the two spectra are in the same position, let's write the expression for each network

Network A

m = 1

sin θ = 1 λ / dA

Network B

m = 2

sin θ = 2 λ / dB

they ask us for the relationship between the distances, we match the equations

λ / dA) = 2 λ / dB

dB / dA = 2

b) let's write the equation of the networks

sin θ = m_A λ / dA

sin θ = m_B λ / dB

we equalize

m_A λ/ dA = m_B λ / dB

we use that

dB / dA = 2

m_A 2 = m_B

therefore the overlapping orders are

Network B Network A

2 1

4 2

6 3

A positron and an electron annihilate each other upon colliding, thereby producing energy in the form of two gamma rays. Assuming that both gamma rays have the same energy (since both particles have the same mass), calculate the wavelength of the electromagnetic radiation used in pm. (1 pm = 10⁻¹² m; mass of electron (amu) = 0.000549)

### Answers

Answer:

2.42631E-13m

Explanation:

First we find the mass defect

Which is m= 0-2(9.10939E-33kg)

= - 1.82188E-30kg

Now find the energy

S

E= mc²=( -18.82188E-30)(2.999792E8)²

= 1.63742E-13J

Thus energy per photon will be

1.63742E-13J/2= 8.18710E-14J

So wavelength is given as

Lambda= hc/E

= (6.62608E-34)(2.997E8)/8.18710J

= 2.42631E-13m

The **wavelength **of **radiation used **to **annihilate **a **positron **and an **electron **is required.

The **wavelength **of the **electromagnetic radiation **used is **2.42 pm.**

The **mass **of **positron **and **electron **are equal

m = **Mass **= [tex]\dfrac{0.000549}{6.022\times 10^{26}}=9.11\times 10^{-31}\ \text{kg}[/tex]

c = **Speed **of **light **= [tex]3\times 10^{8}\ \text{m/s}[/tex]

h = **Planck**'s **constant **= [tex]6.626\times 10^{-34}\ \text{Js}[/tex]

**Total energy **in the collision is

[tex]E_T=mc^2+mc_2\\\Rightarrow E_T=2mc^2\\\Rightarrow E_T=2\times 9.11\times 10^{-31}\times (3\times 10^{8})^2\ \text{J}[/tex]

**Energy released **per **photon **is

[tex]E=\dfrac{E_T}{2}\\\Rightarrow E=\dfrac{2\times 9.11\times 10^{-31}\times (3\times 10^{8})^2}{2}\\\Rightarrow E=9.11\times 10^{-31}\times (3\times 10^{8})^2\ \text{J}[/tex]

**Energy **is given by

[tex]E=\dfrac{hc}{\lambda}\\\Rightarrow \lambda=\dfrac{hc}{E}\\\Rightarrow \lambda=\dfrac{6.626\times 10^{-34}\times 3\times 10^8}{9.11\times 10^{-31}\times (3\times 10^{8})^2}\\\Rightarrow \lambda=2.42\times 10^{-12}\ \text{m}=2.42\ \text{pm}[/tex]

The **wavelength **of the **electromagnetic radiation **used is **2.42 pm.**

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A cannonball is fired on flat ground at 420 m/s at a 53.0° angle. how far away does it land?

### Answers

**Answer:**

17,300 m

**Explanation:**

Using kinematic equations, first find the time it takes to land.

Δy = v₀ t + ½ at²

0 m = (420 sin 53.0° m/s) t + ½ (-9.8 m/s²) t²

t = 0 s or 68.5 s

The horizontal distance it moves in that time is:

Δx = v₀ t + ½ at²

Δx = (420 cos 53.0° m/s) (68.5 s) + ½ (0 m/s²) (68.5 s)²

Δx = 17,300 m

Alternatively, you can use the range equation:

R = v₀² sin(2θ) / g

R = (420 m/s)² sin(2 × 53.0°) / (9.8 m/s²)

R = 17,300 m

The **distance **a cannonball will land if it is **fired **on flat ground at 420 m/s at a 53.0° angle is 17,300 **meters**.

What is the distance?

The complete **movement **of an object, regardless of **direction**, is referred to as **distance**. The amount of ground a thing travels from its starting point to its destination is also referred to as **distance**.

**Given**:

A cannonball is fired on flat ground at 420 m/s at a 53.0° angle,

Calculate the time to land on the ground as shown below,

[tex]\Delta y = v_o t +1/2 at^2[/tex]

0 m = (420 sin 53.0° m/s) t + ½ (-9.8 m/s²) t²

t = 0 s or 68.5 s

Calculate the distance as shown below,

[tex]\Delta x = v_o t +1/2 at^2[/tex]

Δ x = (420 cos 53.0° m/s) (68.5 s) + ½ (0 m/s²) (68.5 s)²

Δ x = 17,300 m

Thus, the total distance covered by the cannonball fired with a speed of 420 m/s is 17300 meters.

To know more about **distance**:

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The coefficient of static friction between a 3.00 kg crate and the 35.0o incline is 0.300. What minimum force F must be applied perpendicularly to the incline to prevent the crate from sliding down

### Answers

Answer:

So the minimum force is

32.2Newton

Explanation:

To solve for the minimum force, let us assume it to be F (N)

So

F=mgsinA

But

=>>>> coefficient of static friction x (F + mgcosA

=>3 x 9.8 x sin35 = 0.3 x (F + 3 x 9.8 x cos35)

So making F subject of formula

F + 24.0 = 56.2

F = 32.2N

What is the tension in the cord after the system is released from rest? Both masses (A and B) are 10-kg.

### Answers

**Answer:**

98 N.

**Explanation:**

Given data: mass= 10 kg, gravity= 9.8 m/s2

required: tension in the cord= ?

solution:

formula of tension= mass x gravity

by putting values of mass and gravity, we get

tension= 10 x 9.8

tension= 98 N. Ans

If the mass of the object which is attached with both ends of cord is 10 kg, so the tension which is a opposite force of weight is 98 N.

In a photoelectric experiment, a metal is irradiated with light of energy 3.56 eV. If a stopping potential of 1.10 V is required, what is the work function of the metal?

### Answers

**Answer:**

The work function is [tex]\phi = 2.46 \ eV[/tex]

**Explanation:**

From the question we are told that

The light energy is [tex]E = 3.56 eV[/tex]

The stopping voltage is [tex]V = 1.10 \ V[/tex]

Generally work function is mathematically represented as

[tex]\phi = E - KE[/tex]

Where KE is the kinetic energy of the ejected electron and it is mathematically represented as

[tex]KE = V * e[/tex]

Where e is the charge on the electron

So

[tex]KE = 1.10eV[/tex]

Thus

[tex]\phi = 3.56eV - 1.10 eV[/tex]

=> [tex]\phi = 2.46 \ eV[/tex]

A person is lying on a diving board 3.00 m above the surface of the water in a swimming pool. She looks at a penny that is on the bottom of the pool directly below her. To her, the penny appears to be a distance of 8.00 m from her.

Required:

What is the depth of the water at this point?

### Answers

**Answer:**

The depth of water at the point is [tex]d_A = 6.55 \ m[/tex]

**Explanation:**

From the question we are told that

The height of the person above water is [tex]d = 3.00 \ m[/tex]

The distance of the coin as seen by the person is [tex]d' = 8.00 \ m[/tex]

Generally the apparent depth is mathematically represented as

[tex]d_a = \frac{d_A}{n}[/tex]

Here [tex]d_A[/tex] is the actual depth of water while n is the refractive index of water with a constant value [tex]n = 1.33[/tex]

Now from the point the person is the apparent depth is evaluated as

[tex]d_a = d'-d[/tex]

=> [tex]d_a = 8 - 3[/tex]

=> [tex]d_a = 5 \ m[/tex]

So

[tex]5 = \frac{d_A}{1.33}[/tex]

=> [tex]d_A = 5 * 1.33[/tex]

=> [tex]d_A = 6.55 \ m[/tex]

Calculate the period of a satellite orbiting the Moon, 98 kmkm above the Moon's surface. Ignore effects of the Earth. The radius of the Moon is 1740 kmkm.

### Answers

Answer:

3.6*10^18s

Explanation:

To find the period of the satellite

We need to apply kephler's third law

Which is

MP² = (4π²/G) d³

d=semi-major axis which is the distance from center of moon = 98km+1740km = 1838km

where M= mass of the moon = 7.3x10^22kg

P=period

G=newtonian gravatational constant= 6.67x10^-11

To find the Period solve for P

P = √[(4π²/G M)xd³]

P=√(4 π²/6.67x10^-22*7.3x10^22kg) x (1.838x10^6m)³]

= 3.6*10^18s

An inductor has inductance of 0.260 H and carries a current that is decreasing at a uniform rate of 18.0 mA/s.

Required:

Find the self-induced emf in this inductor.

### Answers

**Answer:**

**The self-induced emf in this inductor is 4.68 mV.**

**Explanation:**

**The emf in the inductor is given by:**

[tex] \epsilon = -L\frac{dI}{dt} [/tex]

Where:

dI/dt: is the decreasing current's rate change = -18.0 mA/s (the minus sign is because the current is decreasing)

L: is the inductance = 0.260 H

So, the emf is:

[tex] \epsilon = -L\frac{dI}{dt} = -0.260 H*(-18.0 \cdot 10^{-3} A/s) = 4.68 \cdot 10^{-3} V [/tex]

**Therefore, the self-induced emf in this inductor is 4.68 mV. **

I hope it helps you!

The **self-induced emf** in this **inductor** is **4.68 mv.**

Calculation of the emf in the inductor:

Here

E = -LdI/dt

here

dI/dt represents the the **decreasing current's rate change** = -18.0 mA/s

the **minus sign** is due to the **current** is **decreasing**

L represents the **inductance** = 0.260 H

Now the emf should be

= -0260H * (-18.0.10^-3)

= 4.68 mv

hence, The **self-induced emf** in this **inductor** is **4.68 mv.**

Learn more about **current** here: https://brainly.com/question/17080022

What does a constant velocity look like on a displacement vs time graph?

### Answers

**Answer:**

A line with slope equal to the velocity.

**Explanation:**

If one is in the presence of constant velocity, that means that at the quotient between displacement and time elapsed is a constant value, therefore one can write the following equation:

[tex]\frac{displacement}{time} =constant[/tex]

therefore, solving for displacement we get:

[tex]displacement= constant \,*\, time[/tex]

which if plotted with displacement (D) on the vertical axis and time (t) on the horizontal axis, renders a line with slope equal to the constant value of the velocity (v):

[tex]D=v\,*\,t[/tex]

The magnetic field inside a 5.0-cm-diameter solenoid is 2.0 T and decreasing at 4.60 T/s. Part A What is the electric field strength inside the solenoid at a point on the axis

### Answers

**Complete Question **

The magnetic field inside a 5.0-cm-diameter solenoid is 2.0 T and decreasing at 4.60 T/s.

Part A What is the electric field strength inside the solenoid at a point on the axis?

Part B

What is the electric field strength inside the solenoid at a point 1.50 cm from the axis?

**Answer:**

Part A

[tex]E = 0 \ V/m[/tex]

Part B

[tex]E_{15} = 0.0345 \ V/m[/tex]

**Explanation:**

From the question we are told that

The diameter of the solenoid is [tex]d = 5.0 \ cm = 0.05 \ m[/tex]

The magnetic field is [tex]B = 2.0 \ T[/tex]

The rate of the change of the magnetic field is [tex]\frac{dB}{dt} = 4.60 \ T/s[/tex]

The radius of the solenoid is mathematically represented as

[tex]R = \frac{ d}{2}[/tex]

substituting values

[tex]R = \frac{ 5.0 *10^{-2}}{2} = 0.025 \ m[/tex]

Generally the of the solenoid is mathematically represented as

[tex]E = \frac{ r}{2} * |\frac{dB}{dt} |[/tex]

Now at the point on axis is r = 0 given that the axis is the origin so

[tex]E = \frac{ 0}{2} * |\frac{dB}{dt} |[/tex]

[tex]E = 0 \ V/m[/tex]

Now the electric field strength inside the solenoid at a point 1.50cm from the axis is mathematically represented as

[tex]E_{15} = \frac{ 15*10^{-2 }}{2} * |4.60 |[/tex]

[tex]E_{15} = 0.0345 \ V/m[/tex]

Please help!

Much appreciated!

### Answers

Answer:

Ts = 3.0×10¯² sec

Explanation:

From the question given:

Ts = 2π √(4.5×10¯² Kg / 2.0×10³ Kg/s²)

The above expression can be evaluated as follow:

Pi (π) = 3.14

Ts = 2π √(4.5×10¯² / 2.0×10³)

Ts = 2 × 3.14 √(4.5×10¯² / 2.0×10³)

Ts = 6.28 × √(2.25×10¯⁵)

Ts = 6.28 × 4.74×10¯³

Ts = 3.0×10¯² sec

Simple Harmonic Motion: The quartz crystal in a digital watch has a frequency of 32.8 kHz. What is its period of oscillation

### Answers

**Answer:**

Time Period of Oscillation = 3.04 x 10⁻⁵ s

**Explanation:**

The time period of oscillation and the the frequency of oscillation are two inter linked quantities. They are actually the reciprocals of each other. So, the time period of oscillation of quartz crystal is given by the following formula:

**Time Period of Oscillation = 1/Frequency of Oscillation**

where,

Frequency of Oscillation = 32.8 KHz

Frequency of Oscillation = 32800 Hz

Therefore,

**Time Period of Oscillation = 1/32800 Hz**

**Time Period of Oscillation = 3.04 x 10⁻⁵ s**

An unmanned spacecraft has been sent to another planet to detect other life forms that might be quite different from those on Earth. If the probe could only send back one still picture, which property or properties of life would be observable in a picture?

### Answers

**Answer:**

**The presence of water**

**Explanation:**

Any evidence of water that might appear on the still photo would be a clear indication of life on the planet. This is because scientists believe that for life to thrive elsewhere as it has done here on Earth, it needs water. Water is necessary for fertilization of reproductive cells for some organism, and for others it is where their developing young starts life from. For most, all life biochemical system needs a certain level of moisture to function properly.

Which of the following correctly describes the relative air pressure at the center of a hurricane, with respect to the horizontal direction? Group of answer choices low at the surface, high aloft low at the surface and aloft high at the surface and aloft high at the surface, low aloft

### Answers

**Explanation:**

The pressure of hurricane which is high decreases gradually as we move higher . The pressure is maximum at the surface . Hence the relative air pressure is higher at the surface and low at the top . Like wise the pressure is low at the center and keeps on increasing when we move outside . Hence the answer is pressure is high at surface and low aloft.

Unpolarized light with intensity 370W/m2 passes first through a polarizing filter with its axis vertical, then through a second polarizing filter. It emerges from the second filter with intensity 121W/m2 .

What is the angle from vertical of the axis of the second polarizing filter?

Express your answer to two significant figures and include the appropriate units

### Answers

Answer:

Answer:

36°

Explanation:

Using

I= (1/2Io) cos²စ

Then Substituting

121W/m² = 1/2*370W/m²cos²စ

0.8086= cosစ

Cos^-1 0.8086= 36°

When stable air is forced to rise, any clouds that are produced are generally thin and flat lying.

a) true

b) false

### Answers

**Answer:**

**a) true**

**Explanation:**

One of the important factors behind the formation of clouds is the stability of the atmosphere. Air gets condensed with the increase in the height, while it becomes warm with a decrease in its height. A stable air is the type of air that can sink. The air which has low temperature has more density than the air it is surrounded by. When clouds are formed with stable air, the clouds formed are thin and horizontal.

If someone were monitoring your vital signs (like your heart rate, oxygen content in your blood, blood pressure, etc.) every hour in a hospital, you would

likely want them to be both accurate and precise in their measurements. Make an argument for why what you think is more important, accuracy or

precision?

### Answers

Answer:

Accuracy

Explanation:

I think accuracy is more important. When it comes to vital organs in the body, the exactness of getting the measurement is paramount. Accuracy deals with getting very close, almost exact you may say, to a known standard. Precision on the other hand, deals with how easy a measurement can be retaken, reproduced or remade, irrespective of how far or close they are from the accepted norm.

From this, we can agree that precision neglects the most important factor, closeness or say, exactness. Precision isn't bothered by it. And while that can be excused in a few instances, it certainly can not be permitted when it comes to life, or organs of the body

A grating has 320 lines/mm. How many orders of the visible wavelength 551 nm can it produce in addition to the m = 0 order

### Answers

Answer:

6

Explanation:

Given that

dsinθ = mλ,

now, if sinθ = 1, then

m = d / λ, where

m = order of interference

d = distance between the slits

λ = wavelength of light

this is the formula we would use to solve the question

d = 1 / 320 lines/mm

d = 1 / 320*10^3

d = 3.125*10^-6 m

At λ = 551 nm, we have

m = 3.125*10^-6 / 551*10^-9

m = 5.67

5.67 ~ 6

thus, we can say that the orders of visible wavelength 551 nm, can produce is 6

When a p-n-p transistor is operated in saturation region, then its ___________

### Answers

**Answer:**

Base-emitter and Base-collector junctions are forward biased

a supertanker traveling at 7.2 m/s decelerates to a halt in 12 min. Calculate the magnitud of its average decelaration in meters per second squared

### Answers

**Explanation:**

Acceleration is change in velocity over change in time.

a = Δv / Δt

a = (0 m/s − 7.2 m/s) / (12 min × 60 s/min)

a = -0.01 m/s²

A series RLC circuit connected across an ac voltage source has minimum current flowing through the circuit when operating at the resonant frequency. is this statement true or false and why?

### Answers

Answer:

False

Explanation:

This is because Since the current flowing through a series resonance circuit is the product of voltage divided by impedance, at resonance the impedance, Z is at its minimum value, ( =R ). So, the circuit current at this frequency will be at its maximum value of V/R

You are looking down on a single coil in a constant magnetic field B = 1.2 T which points directly into of the screen. The dimensions of the coil go from a = 8 cm and b = 17 cm, to a* = 16 cm and b* = 22 cm in t = 0.04 seconds. If the coil has resistance that remains constant at 1.2 ohms. What would be the magnitude of the induced current in amperes?

### Answers

**Answer:**

The current is [tex]I = 0.5425 \ A[/tex]

**Explanation:**

From the question we are told that

The magnetic field is [tex]B = 1.2 \ T[/tex]

The first length is [tex]a = 8 \ cm = 0.08 \ m[/tex]

The second length is [tex]a^* = 16 \ cm = 0.16 \ m[/tex]

The first width is [tex]b = 17 \ cm = 0.17 \ m[/tex]

The second width is [tex]b^* = 22 \ cm = 0.22 \ m[/tex]

The time interval is [tex]dt = 0.04 \ s[/tex]

The resistance is [tex]R = 1.2 \ \Omega[/tex]

Generally the first area is

[tex]A = a * b[/tex]

=> [tex]A = 0.08 * 0.17[/tex]

=> [tex]A = 0.0136 \ m^2[/tex]

The second area is

[tex]A^* = a^* * b^*[/tex]

=> [tex]A^* = 0.16 * 0.22[/tex]

=> [tex]A^* = 0.0352 \ m^2[/tex]

Generally the induced emf is mathematically represented as

[tex]\epsilon = - \frac{ B * [A^* - A]}{dt}[/tex]

This negative show that it is moving in the opposite direction of the motion producing it

=> [tex]|\epsilon | = \frac{ 1.2 * [ 0.0352-0.0135]}{0.04}[/tex]

=> [tex]|\epsilon | = 0.651 \ V[/tex]

The induced current is

[tex]I = \frac{|\epsilon|}{R}[/tex]

=> [tex]I = \frac{ 0.651}{1.2}[/tex]

=> [tex]I = 0.5425 \ A[/tex]

Which describes the amplitude of a wave when it carries more ene

O It is higher.

O It is lower.

It is darker.

Oli is lighter

### Answers

**Answer:**

It is higher.

**Explanation:**

Hello,

In this case, the quantity of energy that a wave is able to transfer is directly related its amplitude exhibiting that the higher the carried energy, the higher its amplitude and on the flip side, the lower the energy the lower the amplitude, therefore, the answer is **it is higher**. You can verify this on the attached picture.

Regards.

**Answer:**

It is higher.

**Explanation:**

6. Solve (5.87 x 10^7)(4.200 x 10^11). Be

sure your answer is in scientific notation.

Round to two decimal places.

### Answers

**Explanation:**

We need to solve [tex](5.87\times 10^7)(4.2\times 10^{11})[/tex]

Firstly, multiplying 5.87 and 4.2 = 24.654

Now taking exponent of 10.

We know that : [tex]x^a{\cdot} x^b=x^{a+b}[/tex]

It means, [tex]10^7{\cdot} 10^{11}=10^{11+7}=10^{18}[/tex]

So,

[tex](5.87\times 10^7)(4.2\times 10^{11})=24.654\times 10^{18}[/tex]

In scientific notation,

[tex](5.87\times 10^7)(4.2\times 10^{11})=2.4654\times 10^{19}[/tex]

Hence, the value of [tex](5.87\times 10^7)(4.2\times 10^{11})[/tex] is [tex]2.4654\times 10^{19}[/tex]

**Answer:**

**Explanation:**

We need to solve

Firstly, multiplying 5.87 and 4.2 = 24.654

Now taking exponent of 10.

We know that :

It means,

So,

In scientific notation,

Hence, the value of is

An organ pipe open at both ends has two successive harmonics with frequencies of 220 Hz and 240 Hz. What is the length of the pipe? The speed of sound is 343 m/s in air.

### Answers

**Answer:**

The value is [tex]l = 8.58 \ m[/tex]

**Explanation:**

From the question we are told that

The frequencies of two successive harmonics is [tex]f_ a = 220 \ Hz[/tex] , [tex]f_b = 240 \ Hz[/tex]

The speed of sound in the air is [tex]v = 343 \ m/s[/tex]

Generally a harmonic frequency is mathematically represented as

[tex]f_n = \frac{n * v }{2l}[/tex]

here l is the length of the pipe

n is the order of position of the harmonics

Now since we do not know the order of the given harmonic frequencies but we are told that they are successive then the frequencies can be mathematically represented as

[tex]220 = \frac{n * v}{ 2 l }[/tex]

and

[tex]240 = \frac{ (n+1 ) v }{2l}[/tex]

So

[tex]240 - 220 = \frac{ (n+1 ) v }{2l} - \frac{n * v}{ 2 l }[/tex]

[tex]20 = \frac{v}{2l}[/tex]

=> [tex]l = 8.58 \ m[/tex]