Find “d” in the following figure

Answer:

The minimum riding speed relative to the whistle (stationary) to be able to hear the sound at 21.0 kHz frequency is 15.7  m/s

Explanation:

The Doppler shift equation is given as follows;

[tex]f' = \dfrac{v - v_o}{v + v_s} \times f[/tex]

Where:

f' = Required observed frequency = 20.0 kHz

f = Real frequency = 21.0 kHz

v = Sound wave velocity = 330 m/s

[tex]v_o[/tex] = Observer velocity = X m/s

[tex]v_s[/tex] = Source velocity = 0 m/s (Assuming the source is stationary)

Which gives;

[tex]20 = \dfrac{330- v_o}{330+0} \times 21[/tex]

330 - [tex]v_o[/tex] = (20/21)*330

[tex]v_o[/tex] = 330 - (20/21)*330 = 15.7 m/s

The minimum riding speed relative to the whistle (stationary) to be able to hear the sound at 21.0 kHz frequency = 15.7  m/s.

Answer:

y = 64t − 16t²

Explanation:

y = y₀ + v₀ t + ½ at²

y = 0 + 64 t + ½ (-32) t²

y = 64t − 16t²

Answer:

3000 N

Explanation:

as we know that

pressure=force/area

so force=thurst

pressure=thurst/area

thyrst=pressure*area

pressure=150 Nm^-2

area=20m^2

so thurst=150*20=3000 N or 3*10^3 N

Answer:

greatest displacement = 44.1m

initial velocity= 29.4m/s

Explanation:

Greatest displacement

s=1/2at^2

= (9.8/2 ×9)m

= 44.1m

initial velocity

s=ut-1/2at^2

44.1= 3u -(1/2×9.8×9)

44.1=3u-44.1

3u=88.2

u=29.4m/s

Answer:

Earthworm lives in the soil, eats the soil which has organic matter such as decaying vegetation or leaves and crawls. While housefly lives in dirty places, feeds on faeces and flies.

Hope I get a brainliest answer.

Answer: 2 seconds

Explanation:

Since I've only memorized a couple of formulas for these things, I need to do the time first:

I'll use the formula  Distance = (1/2) (acceleration) (time)²

20 m = (1/2) (10 m/s²) (time)²

Time² = (20 m) / (5 m/s²)

Time² = 4 sec²

Time = 2 seconds

Now ...

-- When the ball hits the ground, it has been falling for 2 seconds.

-- Its acceleration has caused its speed to increase by 10 m/s every second.

-- So after 2 seconds, its speed has grown to (2 s) (10 m/s²) = 20 m/s .

Answer:

analysis the force is zero

Explanation:

Let's apply Newton's second law

         F = m a

In this equation we see that the force is directly related to the acceleration, as they indicate that the rocket is far from any planet or star has no force applied to it, therefore they also relate it to zero.

Change we can analyze the exercise with Newton's first law, which indicates that an object maintains its constant speed in a straight line has no forces applied to it.

In either analysis the force is zero

Answer:

It slows down as the cross-section becomes smaller is the correct answer to this question.

Explanation:

Answer:

The safe distance is 199 cm approximately 200 cm

Explanation:

Safe intensity = 1.00 W/m^2

wattage of radar leaked radar = 50.0 W

safe distance from the microwave will be = ?

We know that the intensity of a wave radiated uniformly in all direction is given as

[tex]I[/tex] = [tex]\frac{W}{A}[/tex]

where

W is the wattage of the leaked radar

A is the radial area, which is the area of a sphere that encapsulates the region through which this wave spreads uniformly.

From the equation above,

[tex]A[/tex] = [tex]\frac{W}{I}[/tex] = 50/1 = 50 m^2

But the area of this sphere [tex]A[/tex] = [tex]4\pi r^{2}[/tex]

where

r is the safe distance from the radar source

substituting for the area, we have

50 = 4 x 3.142 x [tex]r^{2}[/tex]

50 = 12.568 [tex]r^{2}[/tex]

[tex]r^{2}[/tex] = 50/12.568 = 3.978

r = [tex]\sqrt{3.978}[/tex] = 1.99 m = 199 cm ≅ 200 cm

Answer:

The correct answer is "By increasing the amount of flooding because of rising sea levels".

Explanation:

Answer:

c) A series of RC circuits.

Answer:

cluttered

Explanation:

The correct word to describe the garage would be cluttered.

A place is said to be cluttered when it is filled with an untidy collection of material things. In this case, the garage is filled with materials such as bike wrenches, tires, frames, etc.

Inviting can also mean tempting, attractive, etc, and has no relevance to the condition of the garage as described in the excerpt.

Dangerous can also mean harmful, and not the right word to describe the garage.

Sparse can also mean scanty, scattered, and would be the opposite of the condition of the garage.

Correct answer: cluttered

Answer:

c.  cluttered

Explanation:

Answer:

165.73 K

Explanation:

The computation of HooRU's temperature is shown below:-

As per the stefan's law, the power radiated by black body radiations which is

[tex]P = eA\sigma T^4[/tex]

where  

A indicates surface area

e indicates emissitivity

T indicates temperature

now, we will put the values in the above equation

[tex]13.5 = 0.209 \times 1.51 \times \sigma \times T^4[/tex]

After solving the above equation we will get temperature which results

= 165.73 K

Therefore for computing the HooRU's temperature we simply applied the above formula.

Answer:

d) All of the above.

Explanation:

Magnetic field lines are formed around an object when there is a magnetic field around the object. From the question, we know that a bar magnet has an electric field. A current carrying loop has a magnetic field around it also. Current carrying straight wires and any conductor generally, carrying an electric current, produces a magnetic field around them. This magnetic field has lines of loos formed close to the material.

Answer:

Destroy information about the speed of the particle

Explanation:

This is according to Heisenberg's Uncertainty Principle states that there is inherent uncertainty in the act of measuring a variable of a particle. Commonly applied to the position and momentum of a particle, the principle states that the more precisely the position is known the more uncertain the momentum is and vice versa.

Answer:

The fly will travel 20 miles before the runners collide with each other.

Explanation:

Since the runners are both traveling at the same speed, they will meet and collide in the exact middle of each other which is 5 miles away from their starting point. Since they are traveling at 5 mph, it will take exactly one hour before they collide. The fly is going 20 mph so it will travel 20 miles before the runners collide in one hour.

Answer:

I think the answer is 8km2

Answer:

Distance = 17km

Displacement = 12.6 km

Explanation:

south 12km

west 4km

north 1km

Total distance = 12 + 4 + 1 = 17km

Total displacement = in picture above.

Answer:

Explanation:

force on charge q  in electric field E = q E

force on charge of bee in given electric field

= 23 x 10⁻¹² x 100

= 23 x 10⁻¹⁰ N

weight of honey bee = .10 x 10⁻³ x 9.8

= 9.8 x 10⁻⁴ N

Ratio of force / weight of bee

= 23 x 10⁻¹⁰  / 9.8 x 10⁻⁴

= 2.347 x 10⁻⁶ .

Answer:

Center of Gravity is the point in a body where the gravitational force may be taken to act.  Center of Buoyancy is the center of gravity for the volume of water which a hull displaces.

Car at rest:

velocity= 0m/s

Acceleration:

0.2m/s²

Since total time:

3 min = 180s

Formula of acceleration:

acceleration = [final velocity - initial velocity] ÷ [total time]

Velocity at end:

0.2m/s² = [final velocity - 0m/s] ÷ [180s]

0.2m/s² × 180s = [final velocity]

[final velocity] = 36m/s

Distance travelled:

Velocity = displacement(distance) ÷ time

36m/s = displacement(distance) ÷ 180s

displacement(distance) = 36m/s × 180s

displacement(distance) = 6480m

Hey I'm sorry but i do not understand why the answer on your worksheet for distance travelled is 3240m... its half of what my answer is...

Answer:

[tex]B=2.025\times 10^{11}\ Pa[/tex]

Explanation:

It is given that,

Speed of P- waves, v = 9 km/s = 9000 m/s

The density of rock is about [tex]2500\ kg/m^3[/tex]

We need to find the average bulk modulus of Earth's crust. Let it is given by B. So,

[tex]v=\sqrt{\dfrac{B}{d}} \\\\B=v^2d\\\\B=(9000)^2\times 2500\\\\B=2.025\times 10^{11}\ Pa[/tex]

So, the bulk modulus of the Earth's crust is [tex]2.025\times 10^{11}\ Pa[/tex].

Answer:

The water is at the top because when the water is stored at the top it does not need as much energy to get it to flow because it will be flowing down and be affected by gravity to make the water pressure.

Answer:

The water is at the top because when the water is stored at the top it does not need as much energy to get it to flow because it will be flowing down and be affected by gravity to make the water pressure.

Explanation:

Answer:

Explanation:

Magnetic field = permeability x turn density x current

Magnetic field = 0.22T

turn density = 4150 /1.6 = 2593.75 t/m

permeability : µ = k µ°

µ°= 4 π 10^-7

k = 1

I = 0.22 / 4 π 10^-7 * 2593.75 = 0.22 10^7 /32594 = 67.497 A

Answer and Explanation:

For computing the displacement at point B and D we need to determine the following calculations

[tex]P_Net = P_C + P_E + P_B[/tex]

= 250 + 350 - 50

= 550 N

Now the deflection for bar AB is

[tex]\delta_{AB} = \frac{PL_{AB}}{AE} \\\\ = \frac{550 \times 500}{6,000 \times 200 \times 10^{3}}[/tex]

Now for bar BC it is

[tex]\delta_{BC} = \frac{PL_{BC}}{AE} \\\\ = \frac{(550 + 50) \times 250}{5,000 \times 200 \times 10^{3}} \\\\ = 1.5 \times 10^{-04} mm[/tex]

And for bar CD it is

[tex]\delta_{CD} = \frac{PL_{CD}}{AE} \\\\ = \frac{(550 -250 + 50) \times 250}{5,000 \times 200 \times 10^{3}} \\\\ = 0.875 \times 10^{-4} mm[/tex]

Now the displacement is as follows

For B

2.292 × 10^{-4} mm

For D, it is

[tex]= 2.292 \times 10^{-4} + 1.5 \times 10^{-4} + 0.875 \times 10^{-4} mm \\\\ = 4.667 \times 10^{-4} mm[/tex]

We simply applied the above formulas for determining the  displacements at points B, D and the same is to be considered  

Answer:

15.96 m³ (corrected to 2 d.p.)

Explanation:

Using idea gas law:

pV = nRT

pressure p = 125000 Pa

volume V = unknown

no. of moles n= 3.27 moles

ideal gas constant R = 8.3145 J K−1 mol−1

Temperature t (in Kelvins) = 15 + 273.15 = 288.15K

125000 x v = 3.27 x 8.3145 x 288.15

v = 15.96 m³ (corrected to 2 d.p.)

Answer:

0.0626 m^3

Explanation:

First, we know that the equation to calculate the behavior of gases is:

PV=nRT

Looking at the problem, we understand that we are needing to solve for V, which means we need to isolate V to solve for it.

The new equation will look something like this:

V=nRT/P

The last step is to simply plug in the remaining variables:

n=3.27

R=8.31 (that is not given but is a standard number that you will always use for "R"/ the ideal gas constant-it helps to right it down somewhere to reference it if you ever need it!)

P=125000

T=288 (the temp needs to be in degrees K, so take 15.0 degrees c and + 273)

Finally, when you input all of those, you will have something that looks like this:

V=(3.27*8.31*288)/125000

V=0.02608205 m^3

V= 0.0626 m^3 (rounded to 3 sig. figs)

I hope this was helpful and easy to understand!

Answer:

t=7.25 sec

Explanation:

840=16t'2,

Answer:

Explanation:

Solution,

When a certain object comes in motion from rest, in the case, initial velocity = 0 m/s

Initial velocity ( u ) = 0 m/s

Final velocity ( v ) = 72 km/h ( Given)

We have to convert 72 km /h in m/s

[tex]72 \: km \: per \: hour[/tex]

[tex] = 72 \times \frac{1000}{60 \times 60} [/tex]

[tex] = 20 [/tex] m/s

Final velocity ( v ) = 20 m/s

Time taken ( t ) = 2 seconds

Acceleration (a) = ?

Now,

we have,

[tex]a = \frac{v - u}{t} [/tex]

[tex]a = \frac{20 - 0}{2} [/tex]

[tex]a = \frac{20}{2} [/tex]

[tex]a = 10 [/tex] m/s ^2

Hope this helps...

Good luck on your assignment..

The correct answer is D. The movement of the molecules will gradually increase.

Explanation:

At the beginning of the model the state of matter of the water is solid, in this, particles have a defined arrangement and are together, which stops particles from moving freely and only allows them to vibrate. However, as the substance is heated the thermal energy (heat) increases in the sample, this causes particles to move more and the arrangement of it changes. Due to this, when the ice melts and there is liquid water particles move more than in solid states, which makes ice lacks a defined shape. Moreover, as the heat continues to increase the thermal and kinetic energy (movement) increases, indeed in gas state (water vapor) particles will move freely. This means the movement or kinetic energy in particles gradually increases in the model.

Answer: D

Explanation:

Answer:

Electric flux;

Φ = 30.095 × 10⁴ N.m²/C

Explanation:

We are given;

Charge on plate; q = 17 µC = 17 × 10^(-6) C

Area of the plates; A_p = 180 cm² = 180 × 10^(-4) m²

Angle between the normal of the area and electric field; θ = 4°

Radius;r = 3 cm = 3 × 10^(-2) m = 0.03 m

Permittivity of free space;ε_o = 8.85 × 10^(-12) C²/N.m²

The charge density on the plate is given by the formula;

σ = q/A_p

Thus;

σ = (17 × 10^(-6))/(180 × 10^(-4))

σ = 0.944 × 10^(-3) C/m²

Also, the electric field is given by the formula;

E = σ/ε_o

E = (0.944 × 10^(-3))/(8.85 × 10^(-12))

E = 1.067 × 10^(8) N/C

Now, the formula for electric flux for uniform electric field is given as;

Φ = EAcos θ

Where A = πr² = π × 0.03² = 9π × 10^(-4) m²

Thus;

Φ = 1.067 × 10^(8) × 9π × 10^(-4) × cos 4

Φ = 30.095 × 10⁴ N.m²/C