5. How does a jack make changing a tire easier?

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:

Option B

Explanation:

Forces acting on the skier-

F1 [tex]= -mg sin(30)[/tex] down the slope  

F2 [tex]= -mg cos(30)[/tex]

F3 = friction force  [tex]= 0.74 mg cos(30)[/tex]  

Net force, down the slope  

[tex]= -mg sin(30)+ 0.74 mg cos(30)\\= mg(.74 cos(30)-sin(30))\\= 0.14mg\\= 1.38m[/tex]

Acceleration [tex]= F/m= 1.38[/tex] m/s2  

Acceleration remains constant, initial speed is 20 m/s

Speed at time t is [tex]1.38t- 20[/tex] m/s

Distance down the slope at time t is [tex]0.69t^2- 20t[/tex]

When the skier stops, her speed is 0. Thus,  

, [tex]1.38t- 20= 0\\t= 20/1.38\\= 14.5[/tex] seconds

Distance travelled in 14.5 seconds [tex]= (0.69)(14.52- 20(14.5)= -145 m[/tex](negative because it is down the slope).

Option B is correct

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:

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:

Current

Explanation:

hope it helps and your day will be full of happiness

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:

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:

Momentum(P) = 1336kgm/s

Explanation:

Momentum is the product of the mass and velocity, therefore Momentum(P) is = mass*velocity. since the mass is given 800kg, all we are left with is the displacement 500m and the time 300s which can be used to find the velocity. so velocity is the displacement divided by the time, ie 500/300 which will give us the velocity 1.67m\s. hence we multiply the mass and the velocity and we'll get 1336kgm/s.

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:

  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:

Energy = 7.83 x 10⁻¹⁹ J

Energy = 6.63 x 10⁻¹⁹ J

Explanation:

The energy of a photon in terms of wavelength can be calculated by the following formula:

[tex]Energy = \frac{hc}{\lambda}\\[/tex]

where,

h = Plank's Constant = 6.63 x 10⁻³⁴ Js

c = speed of light = 3 x 10⁸ m/s

λ = wavelength of light

Now, for λ = 254 nm = 2.54 x 10⁻⁷ m:

[tex]Energy = \frac{(6.63\ x\ 10^{-34}\ Js)(3\ x\ 10^8\ m/s)}{2.54\ x\ 10^{-7}\ m}\\[/tex]

Energy = 7.83 x 10⁻¹⁹ J

Now, for λ = 300 nm = 3 x 10⁻⁷ m:

[tex]Energy = \frac{(6.63\ x\ 10^{-34}\ Js)(3\ x\ 10^8\ m/s)}{3\ x\ 10^{-7}\ m}\\[/tex]

Energy = 6.63 x 10⁻¹⁹ J

Answer:

I_total = ½ m R² + 1/12 m L² + ½ m (a² + b²) + m (x² + y²) ^ {3/2}

Explanation:

The moment of inertia is a scalar quantity, therefore additive, therefore we can find the moments of inertia of each body with respect to the point and add them.

Let's use the parallel axis theorem for the moment of inertia.

          I = [tex]I_{cm}[/tex] + m d²

the moments and inertia of the bodies are

disk                    Icm = ½ m R²

rod                     Icm = 1/12 m L²

rectangle           Icm = 1/12 m (a² + b²)

where a and b are the sides of the rectangle

Let's fix a reference frame on the point body, the length of the rectangle is x and its height y, the total moment of inertia is

          I_total = I_point + I_disco + I_rod + I_rectangular

the moment of inertia of the point is

           I = m r² = m 0

           I_point = 0

disk moment of inertia

suppose it is on the y-axis with x = 0

           I_disco = ½ m R² + m y²

moment inertia rod

located in the opposite corner

The distance from the point to the center of the mass of the rod is

           R = [tex]\sqrt{x^2 +y^2 }[/tex]

           I_varrilla = 1/12 m L² + m ([tex]\sqrt{ x^2 + y^2 }[/tex])

rectangle moment inertia

located on the x axis

            I_rectangle = ½ m (a² + b²) + m x²

we substitute

         I_total = 0 + ½ m R² + m y² + 1/12 m L² + m (Ra x ^ 2 + y²) + ½ m (a² + b²) + m x²

         I_total = ½ m R² + 1/12 m L² + ½ m (a² + b²) + m (x² + y²) + m √(x^2 + y²)

         I_total = ½ m R² + 1/12 m L² + ½ m (a² + b²) + m (x² + y²) ^ {3/2}

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:

Speed = 328 m/s

Explanation:

Given the following data:

Wavelength = 4 m

Frequency = 82 Hz

To find the speed of the radio wave;

Speed = wavelength * frequency

Speed = 4 * 82

Speed = 328 m/s

Therefore, the radio wave is travelling at 328 meters per seconds.

Radio waves can be defined as an electromagnetic wave that has its frequency ranging from 30 GHz to 300 GHz and its wavelength between 1mm and 3000m. Therefore, radio waves are a series of repetitive valleys and peaks that are typically characterized of having the longest wavelength in the electromagnetic spectrum.

Answer:

Block, incline, spring and gravity.

Explanation:

For us to have an energy analysis involving gravitational and spring potential energy, we will need to have a block with specific mass that is held at rest on a frictionless incline plane. Now, the block will compress the spring by a specific length from its equilibrium position and then the block is released to travel a distance right up the slope.

So basically, we will need Block, incline, spring and then gravity for it to move.

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]

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.

Learn more about the unit of measurement here, refer to the link ;

brainly.com/question/12629581

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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:

Explanation:

F=ma.

a=m÷fcos 0

Explanation:

Use the formula:

[tex] e = mc \delta \theta[/tex]

e is the energy released,

m is the mass of water,

c is the specific heat capacity,

δθ is the change in temperature ( 100 - 22)

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: 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:

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:

K.E. = ½ × mv²

= ½ × 120 × (2.5)²

= 60 × 6.25

= 375 J

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:

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

Answer:

its true

Explanation:

The titan mission scheduled for 2026 is a reconnaissance to explore the origin of life. Because, some scientific studies based on titan has showed that there is the presence of some biomolecules. Hence, the statement is true.

The distinctive, abundantly organic planet of Titan is where we will travel next in the solar system, according to NASA. The Dragonfly expedition will fly numerous sorties to sample and inspect locations around Saturn's icy moon, advancing our hunt for the components of life.

In 2026, Dragonfly will take off, and it will land in 2034. The rotorcraft will travel to a great number of Titan's promising sites in search of prebiotic chemical processes that are similar to those on Titan and Earth.

Dragonfly, which has eight rotors and flies like a big drone, is the first multi-rotor vehicle NASA will operate for science on another world. To become the first spacecraft to ever fly its full science payload, it will take advantage of Titan's dense atmosphere, which is four times denser than Earth's. Hence, the statement is true.

Find more on Titan mission :

https://brainly.com/question/13405016

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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.