During the course of a demonstration the professor is called away. When he returns he finds a beaker of water that was at room temperature is now at a slightly higher temperature. There is a stirring rod on the desk and a cigarette lighter. The professor can assume that the temperature increase is due to either heat added or mechanical work done. mechanical work done on the system. heat added to the system.

Answer:

The rate of deceleration is 15 km/h^2.

Explanation:

Since the car comes in 90km/h, it will need deceleration for 15 km/h for 6 seconds to finally stop the car. 15*6=90

Answer: Magnetic Fields

Explanation: A Compass works by detecting the earth's magnetic fields. The earth has a iron core that is part liquid and part solid crystal due to gravitational pressure.

Answer:

1.28 m

Explanation:

As shown in the diagram attached,

According to the principle of moment,

For a body at equilibrium,

Sum of clockwise moment = sum of anticlockwise moment.

Taking moment about the pivot,

W₁(1.6)+W(0.133) = W₂(x)............... Equation 1

Where W₁ = Weight of the first child, Wₓ = Weight of the seesaw, W₂ = weight of the second child, x = distance of the second child from the pivot.

But,

W = mg

Where g = 9.8 m/s², m = mass of the body

Therefore,

W₁ = 26×9.8 = 254.8 N,

Wₓ = 18×9.8 = 176.4 N

W₂ = 34.4×9.8 = 337.12 N

Substitute these values into equation 1

(254.8×1.6)+(176.4×0.133) = 337.12(x)

407.68+23.4612 = 337.12x

337.12x = 431.1412

x = 431.1412/337.12

x = 1.2789

x ≈ 1.28 m

Answer:

0.2 km/minute or 12 km/h

Explanation:

All you have to do is divide distance by time to find the speed. 1/5 km/min is the speed into which we simplify to 0.2 km/min. I then multiplied by 60(numerator and denominator) since there are 60 minutes in an hour to get 12 km/h.

Answer:

tbh i think hes right

Explanation:

The femur would be shortened by 0.0434 cm by a load of 600N.

The total applied force per unit of area is known as the pressure.

The pressure depends both on externally applied force as well the area on which it is applied.

The mathematical expression for the pressure

Pressure = Force /Area

As given in the problem assume the femur has a diameter of 3.0cm and a hollow center of 0.8cm diameter and a length of 50cm.if it is supporting a load of 600N,

The stress in the femur = force /area

                                       =600 / π(.004²-.0015²)

                                        = 13.89 ×10⁶ Pa

The length reduced by the load = PL/AE

                                                      = 13.89 ×10⁶ ×50/ 16 × 10⁹ cm

                                                       =0.0434 cm

The femur would be shortened by 0.0434 cm by a load of 600N.

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Answer:

The correct answer is "3899.92 N".

Explanation:

The given values are:

Force,

[tex]F_{app}=58 N[/tex]

Ratio,

[tex]\frac{R_2}{R_1}=8.2[/tex]

As we know,

Area, [tex]A=\pi r^2[/tex]

or,

⇒  [tex]\frac{F_2}{F_1} =\frac{A_2}{A_1}[/tex]

On substituting the value of "A", we get

⇒  [tex]\frac{F_2}{F_1} =\frac{\pi r_2^2}{\pi r_1^2}[/tex]

⇒  [tex]\frac{F_2}{F_1} =\frac{r_2^2}{r_1^2}[/tex]

On applying cross-multiplication, we get

⇒  [tex]F_2=F_1\times (\frac{r_2}{r_1} )^2[/tex]

On substituting the given values, we get

⇒       [tex]=58\times (8.2)^2[/tex]

⇒       [tex]=58\times 67.2[/tex]

⇒       [tex]=3899.92 \ N[/tex]

Answer:

  L = 0.7 m

Explanation:

This is a resonance exercise, in this case the air-filled pipe is open at both ends, therefore we have bellies at these points.

          λ / 2 = L                       1st harmonic

          λ = L                            2nd harmonic

          λ = 2L / 3                    3rd harmonic

         λ =  2L / n                    n -th harmonic

the speed of sound is related to wavelength and frequencies

           v =λ f

            f = v /λ

we substitute

            f = v n / 2L

the speed of sound in air is v = 343 m / s

suppose that the frequency of f = 980Hz occurs in harmonic n

            f₁ = v n / 2L

            f₂ = v (n + 1) / 2L

            f₃ = v (n + 2) / 2L

we substitute the values

             2 980/343  =  n / L

              2 1260/343 = (n + 1) / L

               2 1540/343 = (n + 2) / L

we have three equations, let's use the first two

              5.714 = n / L

              7.347 = (n + 1) / L

we solve for L and match the expressions

              n / 5,714 = (n + 1) / 7,347

              7,347 n = 5,714 (n + 1)

              n (7,347 -5,714) = 5,714

              n = 5,714 / 1,633

              n = 3.5

as the number n must be integers n = 4 we substitute in the first equation

              L = n / 5,714

              L = 0.7 m

Answer:

The angular speed of the blade is of 166.67 rad/min

If a radial saw has a blade with a 9-in. radius. Suppose that the blade spins at 1000 rpm then the angular speed of the blade would be 104.72 rad/seconds.

The total distance covered by any object per unit of time is known as speed. It depends only on the magnitude of the moving object. The unit of speed is a meter/second. The generally considered unit for speed is a meter per second.

The mathematical expression for speed is given by

speed = total distance /Total time

As given in the problem If a radial saw has a blade with a 9-in. radius. Suppose that the blade spins at 1000 rpm then we have to find the angular speed of the blade,

the angular speed of the blade (ω) = 2πN/60

                                                          =2×π×1000/60

                                                          = 104.72 rad/seconds

Thus, the angular speed of the radial saw would be 104.72 rad/seconds

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Answer:

0.5429 m/s^2

Explanation:

velocity of waterjet = 18 m/s

diameter of water jet ( d ) = 4 cm = 0.04 m

mass of vertical plate(m) = 750 kg

Determine the acceleration of plate when the jet first strikes ( i.e. t = 0 )

first we will determine the impact force

F = β*A*V^2 ----- ( 1 )

where ; β = 1000 kg/m^3  ,  A = π/4 * d^2 , V = 18 m/s

input values into equation 1

F = 407.15 N

finally determine the acceleration at t = 0

F = m*a

a = F / m =  407.15 / 750 = 0.5429 m/s^2

Answer:

Current

Explanation:

hope it helps and your day will be full of happiness

Explanation:

Newton's second law of motion states F=ma which means force is equal to mass multiplied by acceleration which in simple terms means If you give mass force it will accelerate the concept of force in physics is any interaction that when unopposed will change the motion of an object.

In the model 1 AU = 100 meters (the length of a football field) , then mars would be 150 meters far from the school, therefore the correct answer is option C.

A unit of measurement is a specified magnitude of a quantity that is established and used as a standard for measuring other quantities of the same kind. It is determined by convention or regulation.

As given in the problem the  Earth Science students are making a human-scale model of the solar system out on the school playground. The school itself represents the Sun. In the model 1 AU = 100 meters,

As given in the table marks is 1.5 AU far from Mars,

1 AU = 100 meters

1.5 AU = 1.5 × 100

           = 150 meters

Thus, mars would be 150 meters far from the school, therefore the correct answer is option C.

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Answer:

It's important

Explanation:

Mental wellness is critical to overall physical health. Participating in recreational activities helps manage stress. Taking time to nurture oneself provides a sense of balance and self-esteem, which can directly reduce anxiety and depression.

Answer:

Mental wellness is critical to overall physical health. Participating in recreational activities helps manage stress. Taking time to nurture oneself provides a sense of balance and self-esteem, which can directly reduce anxiety and depression.

Explanation:

Answer:

Wavelength = 1.36 * 10^{-34} meters

Explanation:

Given the following data;

Mass = 0.113 kg

Velocity = 43 m/s

To find the wavelength, we would use the De Broglie's wave equation.

Mathematically, it is given by the formula;

[tex] Wavelength = \frac {h}{mv} [/tex]

Where;

h represents Planck’s constant.

m represents the mass of the particle.

v represents the velocity of the particle.

We know that Planck’s constant = 6.6262 * 10^{-34} Js

Substituting into the formula, we have;

[tex] Wavelength = \frac {6.6262 * 10^{-34}}{0.113*43} [/tex]

[tex] Wavelength = \frac {6.6262 * 10^{-34}}{4.859} [/tex]

Wavelength = 1.36 * 10^{-34} meters

Answer:

K.E. = ½ × mv²

= ½ × 120 × (2.5)²

= 60 × 6.25

= 375 J

Answer:

I1 = ε/R1

I2 = ε/R2

I3 = ε/R3

Explanation:

From the image, we see that the resistors are connected in parallel. This means that the voltage passing through them is the same.

Now, formula for current is; I = V/R

In this case, V which is voltage is denoted by ε.

Thus;

I1 = ε/R1

I2 = ε/R2

I3 = ε/R3

Answer:

0.174 plasma

[tex]$5.85 \times 10^{-4}$[/tex] flame

Explanation:

Given :

Energy :

[tex]$\Delta E=3.371 \times 10^{-19} $[/tex] J per atom

[tex]$g^*=2$[/tex] (degenraci of excited state)

g = 1  (degenraci of excited state)

Boltzmann Distribution

[tex]$\frac{N^*}{N}=\frac{g^*}{g}e^{-\frac{\Delta E}{kT}}$[/tex]

where,

[tex]$N^*$[/tex] = atoms in excited state

N = atoms in lower energy level

k = [tex]$1.38 \times 10^{-23}$[/tex]  J/K

Therefore,

Relative population in plasma

T = 10,000 K

[tex]$\frac{N^*}{N}=\frac{g^*}{g}e^{-\frac{\Delta E}{kT}}$[/tex]

[tex]$\frac{N^*}{N}=\frac{2}{1}e^{-\frac{-3.37\times 10^{-19}}{1.38 \times 10^{-23} \times 10000}}$[/tex]

[tex]$\frac{N^*}{N}=2 \times e^{-2.44275}$[/tex]

[tex]$\frac{N^*}{N}=2 \times 0.8692$[/tex]

[tex]$\frac{N^*}{N}=0.1738$[/tex]

Relative population in flame    

T = 3000

[tex]$\frac{N^*}{N}=\frac{g^*}{g}e^{-\frac{\Delta E}{kT}}$[/tex]

[tex]$\frac{N^*}{N}=\frac{2}{1}e^{-\frac{-3.371\times 10^{-19}}{1.38 \times 10^{-23} \times 3000}}$[/tex]

[tex]$\frac{N^*}{N}=2 \times e^{-8.1425}$[/tex]

[tex]$\frac{N^*}{N}=2 \times 2.9090 \times 10^{-4}$[/tex]

[tex]$\frac{N^*}{N}=5.85 \times 10^{-4}$[/tex]

Answer: long pipe is used to increase torque and reduce force needed.

Explanation: A torque is needed to open bolt. torque = F·r, if

R increases, Force F needed to open bold is smaller.

Problem is a worn bolt may break down. It sometimes I send useful to heat bolt instead using too much power.

Answer:

120 kg•m/s.

Explanation:

From the question given above, the following data were obtained:

Case 1

Mass of object = M

Velocity of object = V

Momentum = 15 kg•m/s

Case 2

Mass of object = 2M

Velocity of object = 4V

Momentum = ?

Momentum is defined as follow:

Momentum = mass × velocity

The momentum of object in case 2 can be obtained as follow:

From case 1

Momentum = mass × velocity

15 = M × V

15 = MV ....... (1)

From case 2:

Momentum = mass × velocity

Momentum = 2M × 4V

Momentum = 8MV ....... (2)

Finally , substitute the value of MV in equation 1 into equation 2.

Momentum = 8MV

MV = 15

Momentum = 8 × 15

Momentum = 120 kg•m/s

Therefore, an object with a mass of 2M and 4V would have a momentum of 120 kg•m/s

Answer:

Resistance in circuit = 0.53 ohm (Approx.)

Explanation:

Given:

Flow of current in circuit = 15 amp

Potential difference = 8 Volts

Find:

Resistance in circuit

Computation:

In an electrical system, resistance is a stopper of a material to electric current.

Resistance in circuit = Potential difference / Flow of current in circuit

Resistance in circuit = 8 / 15

Resistance in circuit = 0.53 ohm (Approx.)

Answer:

"2580 Hz" is the correct solution.

Explanation:

According to the question,

The path difference,

= [tex]4.4 - 3.6[/tex]

= [tex]0.80 \ m[/tex]

Speed,

= 344 m/s

For constructive interference,

⇒  [tex]Path \ difference =n\times \frac{Speed}{frequency}[/tex]

On substituting the values, we get

⇒  [tex]0.80=n\times \frac{344}{frequency}[/tex]

⇒  [tex]frequency=n\times 430[/tex]

⇒                [tex]n=\frac{frequency}{430}[/tex]

If the frequency range is,

f = 2193,

⇒  [tex]n=\frac{2193}{430}[/tex]

        [tex]=5.1[/tex]

If the frequency range is,

f = 2967,

⇒  [tex]n=\frac{2967}{430}[/tex]

        [tex]=6.9[/tex]

hence,

For n = 6, the frequency will be:

⇒  [tex]Frequency=n\times 430[/tex]

                       [tex]=6\times 430[/tex]

                       [tex]=2580 \ Hz[/tex]

Answer:

Explanation:

Money is used to cover the explicit cost. They're what we're used to seeing, and they're easy to identify. There are several classifications for explicit costs; we can distinguish between fixed and variable costs, as well as direct and indirect costs. Raw materials, manpower, indirect production costs, and so on are all factors that contribute to its expense.

The opportunity cost of using a resource is the amount of money paying for it that might have been used on something else.

Alternative benefit options or money that we miss earning by doing such business acts are referred to as opportunity costs.

When a corporation foregoes an alternative action but does not make a bill, it incurs implicit costs. These are a company's hidden costs:

1. The use of the firm's own funds (money or assets).

2. The owner's capital, savings, and financial services are used.

From the given information:

The total explicit cost = Rent + office supplies + office staff + telephone expense

=$( 14000 + 1000 + 24000 + 4500)

= $43500

The total implicit cost = forgone salary + forgone interest

= $40000 + 7% of $5000

= $40000 + 350

=$40350

Explanation:

a hot toothbrush. ......lol

Answer:

0.525 m

Explanation:

From the question,

In an open pipe,

v = λf................... Equation 1

Where v = speed of sound in the pipe, f = frequency, λ = wave length.

But,

λ = 2l................ Equation 2

Where l = length of the pipe

Substitute equation 2 into equation 1

v = 2lf.............. Equation 3

make l the subject of the equation

l = v/2f............. Equation 4

Given:

v ≈ (331+0.60T) m/s at T = 26°C

v ≈ (331+0.60×26) ≈ 346.6 m/s

f = 330 Hz.

Substitute these values into equation 4

l = 346.6/(2×330)

l = 346.6/660

l = 0.525 m

Hence the length of the pipe is 0.525 m

Explanation:

if the mass or both of the objects is doubled, then the force of gravity between them is quadrupled and so on. Since gravayional force is inversely proportional to the square of separation distance between two interacting objects, more separation distance will result in weaker gravitational forces.

Answer:

a) [tex] v = 2.36 \cdot 10^{7} m/s [/tex]

b) [tex] B = 3.80 \cdot 10^{-4} T [/tex]

c) [tex] f = 1.06 \cdot 10^{7} Hz [/tex]

d) [tex] T = 9.43 \cdot 10^{-8} s [/tex]

Explanation:

a) We can find the electron's speed by knowing the kinetic energy:

[tex] K = \frac{1}{2}mv^{2} [/tex]

Where:    

K: is the kinetic energy = 1.59 keV

m: is the electron's mass = 9.11x10⁻³¹ kg

v: is the speed =?

[tex] v = \sqrt{\frac{2K}{m}} = \sqrt{\frac{2*1.59 \cdot 10^{3} eV*\frac{1.602 \cdot 10^{-19} J}{1 eV}}{9.11 \cdot 10^{-31} kg}} = 2.36 \cdot 10^{7} m/s [/tex]

b) The electron's speed can be found by using Lorentz's equation:

[tex] F = q(v\times B) = qvBsin(\theta) [/tex]   (1)

Where:

F: is the magnetic force

q: is the electron's charge = 1.6x10⁻¹⁹ C

θ: is the angle between the speed of the electron and the magnetic field = 90°

The magnetic force is also equal to:

[tex] F = ma_{c} = m\frac{v^{2}}{r} [/tex]   (2)

By equating equation (2) with (1) and by solving for B, we have:

[tex] B = \frac{mv}{rq} = \frac{9.11 \cdot 10^{-31} kg*2.36 \cdot 10^{7} m/s}{0.354 m*1.6 \cdot 10^{-19} C} = 3.80 \cdot 10^{-4} T [/tex]

c) The circling frequency is:

[tex] f = \frac{1}{T} = \frac{\omega}{2\pi} = \frac{v}{2\pi r} [/tex]

Where:

T: is the period = 2π/ω

ω: is the angular speed = v/r

[tex] f = \frac{v}{2\pi r} = \frac{2.36 \cdot 10^{7} m/s}{2\pi*0.354 m} = 1.06 \cdot 10^{7} Hz [/tex]

d) The period of the motion is:

[tex] T = \frac{1}{f} = \frac{1}{1.06 \cdot 10^{7} Hz} = 9.43 \cdot 10^{-8} s [/tex]

I hope it helps you!

Answer:

X = 50 g

Explanation:

Please see attached photo for explanation.

From the attached photo,

Anticlock–wise moment = X × 20

Clockwise moment = 100 × 10

Anticlock–wise moment = clockwise moment

X × 20 = 100 × 10

X × 20 = 1000

Divide both side by 20

X = 1000 / 20

X = 50 g

Therefore, the value of X is 50 g

Answer:

Explanation:

F=ma.

a=m÷fcos 0