what does it mean to "conserve money" or to "conserve resources"

Answer:

The time taken for the train to cross the bridge is 9.01 s

Explanation:

Given;

length of the train, L₁ = 90 m

length of the bridge, L₂ = 0.06 m

speed of the train, v = 10 m/s

Total distance to be traveled, = L₁ + L₂

                                                  = 90 m + 0.06 m

                                                   = 90.06 m

Time of motion = Distance / speed

Time of motion = 90.06 / 10

Time of motion = 9.006 s ≅ 9.01 s

Therefore, the time taken for the train to cross the bridge is 9.01 s

Answer:

D - 3/5r

Explanation:

Khan Academy

Answer:

-2.27

Explanation:

Got it right on Acellus

Answer:

-2.27

Explanation:

Acellus

Answer:

When the obstacle is fixed, the law of action and reaction, makes the reflected wave is inverted.

When the obstacle is mobile, he mobile point, it moves in the direction of the wave, therefore there is no inversion of it.

Explanation:

Waves when they reach an obstacle behave like a shock, therefore if we use the conservation of momentum the wave must reverse its speed, this explains that the speed changes sign, the wave is reflected.

When the obstacle is fixed, the wave when it reaches the obstacle exerts a force on the point, by the law of action and reaction the point exerts on the wave a force of equal magnitude but in the opposite direction, this reaction force which makes the reflected wave is inverted.

When the obstacle is mobile, this is without friction, when the wave arrives it exerts a force on the mobile point, it moves in the direction of the wave, reaching the maximum amplitude of the incident wave, when it is reflected the point begins to go down along with the wave, therefore there is no inversion of it.

Answer:

4.5 W

Explanation:

Applying,

P = V²/(R₁+R₂).................. Equation 1

Where P = Power, V = Voltage, R₁ and R₂ = values of the two resistor.

From the question,

Given: V = 9.00 V, R₁ = 7.00 Ω, R₂ = 11.00  Ω

Substitute these values into equation 1

P = 9²/(7+11)

P = 81/(18)

P = 4.5 Watt.

Hence the power dessipated by the two resistors is 4.5 watt

Answer:

(AIDS) is a chronic, potentially life-threatening condition caused by the human immunodeficiency virus (HIV). By damaging your immune system, HIV interferes with your body's ability to fight infection and disease. HIV is a sexually transmitted infection (STI). It can also be spread by contact with infected blood or from mother to child during pregnancy, childbirth or breast-feeding.

Explanation:

To help prevent the spread of HIV: 1. Use treatment as prevention (TasP). If you're living with HIV, taking HIV medication can keep your partner from becoming infected with the virus.

Answer:

Momentum = 4455 Ns

Explanation:

Given the following data;

Force = 450 N

Time = 9.9 seconds

To find the momentum;

According to Newton's second law of motion in terms of momentum states that the net force acting on an object is equal to change in momentum divided by time.

Mathematically, it is given by the formula;

Net Force = change in momentum/time

Momentum = force * time

Substituting into the formula, we have;

Momentum = 450 * 9.9

Momentum = 4455 Ns

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it's on the screenshot, apparently it was inappropitae so i couldnt submit it here

Answer:

1) Buoyant force, 2) sinks, 3) equilibrium, 4) fleet , 5) LIFT force

Explanation:

A body in a fluid is subjected to two forces, its weight and the thrust

           sun F = B - W

the em

bid is always vertical and contrary to weight, let's analyze and complete the different situations presented

1) Buoyant force

2) sinks           B <W

3) equilibrium B = W

4) fleet             B> W

5) by the sum of two forces:

* Thrust, but the density of air is much less than the density of water, therefore the thrust in the air is less.

* The other force in airplanes the lift force given by the difference in the path of the air when the plane moves, which translates into a pressure difference between the upper part of the wing and the lower part, it is force is called   LIFT force

Answer:

thermal  energy  or proportional  energy

Explanation:

when the  wood is moved the energy is changed thoughout the wood and it would be the same as the pipe and water

Answer:

4.96 eV

Explanation:

Recall the Einstein photoeletric equation;

KE = E - Wo

Where;

KE = kinetic energy of the ejected photoelectron

E= energy of the incident photon

Wo = Work function

But

KE = eV= 1.6 * 10^-19 C * 7 V /1.6 * 10^-19 C = 7 eV

E = hf/e = 6.6 * 10^-34 * 2.9 ✕ 10^15 Hz/1.6 * 10^-19

E = 11.96 eV

Hence;

Wo = E - KE

Wo = 11.96 eV - 7eV

Wo = 4.96 eV

Answer:A

Explanation:

The wavelength of the sound wave will be 3 meters.

The wavelength of any wave is defined as the distance between two max adjacent amplitudes, or the distance between two successive troughs or crest.

Now it is given that:

Distance =9 meters

time = 3 seconds

pitch=1/3 seconds

The velocity of  the sound will be

[tex]V=\dfrac{d}{t}=\dfrac{9}{3}=3\ \frac{m}{s}[/tex]

Now from the question the wavelength of the sound wave if the velocity of the wave remains constant but the pitch is tripled

so  [tex]f=3\times \dfrac{1}{3}=1 herts[/tex]

Now the velocity of the sound will be

[tex]v=f\times \lambda[/tex]

[tex]\lambda=\dfrac{v}{f}=\dfrac{3}{1}=3\ m[/tex]

Thus the wavelength of the sound wave will be 3 meters.

To know more about wavelength, follow

https://brainly.com/question/10728818

Answer:

A light-year is the distance light travels in one year. How far is that? Multiply the number of seconds in one year by the number of miles or kilometers that light travels in one second, and there you have it: one light-year. It's about 5.88 trillion miles (9.5 trillion km).

Explanation:

Answer:

1. The three main acidic gases responsible for lowering the pH of rainwater are non-metal oxides produced by the burning of fossil fuels like coal, oil and natural gas. Sulfur dioxide is produced when fossil fuels containing sulfur impurities are burned.

2. A great way to reduce acid rain is to produce energy without using fossil fuels. Instead, people can use renewable energy sources, such as solar and wind power. Renewable energy sources help reduce acid rain because they produce much less pollution.

3. The pH scale is logarithmic, meaning that an increase or decrease of an integer value changes the concentration by a tenfold. For example, a pH of 3 is ten times more acidic than a pH of 4.

Answer:

Density = 0.243 g/cm³

Explanation:

Volume of cork = 23.5 cm³

Mass = 5.7 g

To find the density of the cork;

Density can be defined as mass all over the volume of an object.

Simply stated, density is mass per unit volume of an object.

Mathematically, density is given by the formula;

[tex]Density = \frac{mass}{volume}[/tex]

Substituting into the formula, we have;

Density = 5.7/23.5

Density = 0.243 g/cm³

Answer:

Explanation:

Newton's first law of motion states that an object in motion stays in motion. The orange is moving and then the tray stops making the orange move forward because of inertia.

Answer:

The off the tray due to the inertia of motion

Explanation:

As we suddenly stop, the tray and our body comes to rest instantly they are in contact. The placed on tray and keeps moving due to the inertia of motion and hence roll of your tray

Answer:

The intensity of the net electric field will:

[tex]E_{net}=E_{1}+E_{2}=2.52*10^{7}\: N/C[/tex]

Explanation:

Here we need first find the electric field due to the first charge at the midway point.

The electric field equation is given by:

[tex]|E_{1}|=k\frac{q_{1}}{d^{2}}[/tex]

Where:

So, we will have:

[tex]|E_{1}|=(9*10^{9})\frac{20*10^{-6}}{0.1^{2}}[/tex]

[tex]|E_{1}|=1.8*10^{7}\: N/C[/tex]

The direction of E1 is to the right of the midpoint.

Now, the second electric field is:

[tex]|E_{2}|=k\frac{q_{2}}{d^{2}}[/tex]

[tex]|E_{2}|=(9*10^{9})\frac{8*10^{-6}}{0.1^{2}}[/tex]

[tex]|E_{2}|=7.2*10^{6}\: N/C[/tex]

The direction of E2 is to the right of the midpoint because the second charge is negative.

Finally, the intensity of the net electric field will:

[tex]E_{net}=E_{1}+E_{2}=2.52*10^{7}\: N/C[/tex]

I hope it helps you!

The net electric field midway between these two charges is 2.52 x 10⁷ N/C.

The electric field strength between two point charges is the force per unit charge.

Electric field strength due to +20.0 μC charge

[tex]E _1 = \frac{kq_1}{r^2} \\\\E_ 1 = \frac{9 \times 10^9 \times 20 \times 10^{-6}}{(0.1)^2} \\\\E _1 = 18 \times 10^6 \ N/C[/tex]

Electric field strength due to -8μC charge

[tex]E _2 = \frac{kq_2}{r^2} \\\\E_ 2 = \frac{9 \times 10^9 \times 8 \times 10^{-6}}{(0.1)^2} \\\\E _2 = 7.2 \times 10^6 \ N/C[/tex]

The net electric field midway between these two charges is calculated as follows;

[tex]E_{net} = 18 \times 10^6 \ + \ 7.2 \times 10^6\\\\E_{net} = 25.2 \times 10^6 \ N/C\\\\E_{net} = 2.52 \times 10^7 \ N/C[/tex]

Learn more about electric field here: https://brainly.com/question/14372859

Answer: But what about beer-brewing, crop breeding, and the antibiotic penicillin? These processes and products – some of which have been around for thousands of years – are also examples of biotechnology.

Explanation:

Specifically, industrial biotechnology uses enzymes and micro-organisms to make bio-based products in sectors such as chemicals, food ingredients, detergents, paper, textiles and biofuels. ... Since that time, industrial biotechnology has produced enzymes for use in our daily lives and for the manufacturing sector.

Answer:

15 J

Explanation:

Work = Force x Distance

15= 30 x 0.5

Have a blessed day!

Answer:Pravat did 15 J of work

Explanation:

Answer:

(i) Please find attached the required velocity time graphs plotted with MS Excel

(ii) The velocity of vehicle A at the 18th second = 20 m/s

The velocity of vehicle B at the 18th second = 0 m/s

(iii) The distance between the two vehicles at the moment in (ii) above is 60 meters

Explanation:

The given parameters of the motion of vehicles A and B are;

The acceleration of vehicles A and B = Uniform acceleration starting from rest

The maximum velocity attained by vehicle A = 30 m/s

The time it takes vehicle A to attain maximum velocity = 10 s

The maximum velocity attained by vehicle B = 30 m/s

The time it takes vehicle B to attain maximum velocity = The time it takes vehicle A to attain maximum velocity = 10 s

The time duration vehicle A maintains its maximum velocity = 6 s

The time duration vehicle B maintains its maximum velocity = 4 s

(i) From the question, we get the following table;

[tex]\begin{array}{ccc}Time &V_A&V_B\\0&0&0\\10&30&40\\14&30&40\\16&30&20\\18&20&0\\22&0&\end{array}[/tex]

From the above table the velocity time graphs of vehicles A and B is created with MS Excel and can included here

(ii) The velocity of vehicle A at the start = 0 m/s

After accelerating for 10 seconds, the velocity of vehicle A = The maximum velocity of vehicle A = 30 m/s

The maximum velocity is maintained for 6 seconds which gives;

At 10 s + 6 s = 16 s, the velocity of vehicle A = 30 m/s

The time it takes vehicle A to decelerate to rest = 6 s

The deceleration of vehicle A, [tex]a_A[/tex] = (30 m/s - 0 m/s)/(6 s) = 5 m/s²

Therefore, we get;

v = u - [tex]a_A[/tex]·t

At the 18th second, the deceleration time, t = 18 s - 16 s = 2 s

u = 30 m/s

∴ v₁₈ = 30 - 5 × 2 = 20

The velocity of vehicle A at the 18th second, [tex]V_{18A}[/tex] = 20 m/s

For vehicle B, we have;

At the 14th second, the velocity of vehicle B = 40 m/s

Vehicle B decelerates to rest in, t = 4 s

The deceleration of vehicle B, [tex]a_B[/tex] = (40 m/s - 0 m/s)/(4 s) = 10 m/s²

For vehicle B, at the 18th second, t = 18 s - 14 s = 4 s

∴ [tex]v_{18B}[/tex] = 40 m/s - 10 m/s² × 4 s = 0 m/s

The velocity of the vehicle B at 18th second, [tex]v_{18B}[/tex] = 0 m/s

(iii) The distance covered by vehicle A up to the 18th second is given by the area under the velocity-time graph as follows;

The area triangle A₁ = (1/2) × 10 × 30 = 150

Area of rectangle, A₂ = 6 × 30 = 180

Area of trapezoid, A₃ = (1/2) × (30 + 20) × 2 = 50

The distance covered in the 18th second by vehicle [tex]S_A[/tex] = A₁ + A₂ + A₃

∴ [tex]S_A[/tex] = 150 + 180 + 50 = 380

The distance covered in the 18th second by vehicle [tex]S_A[/tex] = 380 m

The distance covered by the vehicle B in the 18th second is given by the area under the velocity time graph of vehicle B as follows;

Area of trapezoid, A₅ = (1/2) × (18 + 4) × 40 = 440

The distance covered by the trapezoid, [tex]S_B[/tex] = 440 m

The distance of the two vehicles apart at the 18t second, [tex]S_{AB}[/tex] = [tex]S_B[/tex] - [tex]S_A[/tex]

∴ [tex]S_{AB}[/tex] = 440 m - 380 m = 60 m

The distance of the two vehicles from one another at the 18th second, [tex]S_{AB}[/tex] = 60 m.

Answer:

A microwave

Explanation

The human retina can only detect incident light that falls in waves 400 to 720 nanometers long, so we can't see microwave or ultraviolet wavelengths. This also applies to infrared lights which has wavelengths longer than visible and shorter than microwaves, thus being invisible to the human eye.

Answer:

C.) Microwave

Explanation:

USAtestprep

Answer:

The velocity of one of the trains is 15 m/s

The velocity of the other train 5 m/s

Explanation:

The given parameters of the two trains and the motion of the trains are;

The length of each train, l = 100 m

The time it takes one train to overtake the other, Δt₁ = 20 s

The time it takes the one train to cross the other, Δt₂ = 10 s

Let 'v₁' represent the velocity of one of the trains, and let 'v₂' represent the velocity of the other train, we have;

When one train overtakes the other, the trains are moving in the same direction and the relative velocity of the overtaking train, v = v₁ - v₂

The distance the train travels when overtaking or crossing, d = 2 × l

∴ d = 2 × 100 m = 200 m

d = 200 m

Therefore, we get;

v = v₁ - v₂ = d/Δt₁ = (200 m)/(20 s) = 10 m/s

∴ v₁ - v₂ = 10 m/s                     [tex]{}[/tex]                    Equation (1)

When one train crosses the other train, the trains are moving in opposite directions on the different tracks, therefore, we have;

For the overtaking trains, v = v₁ + v₂ = d/Δt₂ = (200 m)/(10 s) = 20 m/s

∴ v₁ + v₂ = 20 m/s                              [tex]{}[/tex]          Equation (2)

Adding equation (1) to equation (2) gives;

v₁ - v₂ + v₁ + v₂ = 2·v₁ = 10 m/s + 20 m/s = 30 m/s

∴ v₁ = 30 m/s/2 = 15 m/s

The velocity of one of the trains, v₁ = 15 m/s

From equation (2), we  have;

v₁ + v₂ = 20 m/s

v₂ = 20 m/s - v₁

∴ v₂ = 20m/s - 15 m/s = 5 m/s

The velocity of the other train, v₂ = 5 m/s.

Answer:

hope it is helpful to you ☺️☺️✌️

Answer:

Hooke's law, given by [tex]F=-kx[/tex] is denoted with a negative sign to regard that the direction of restoring force that occurs opposite in direction of the force that caused the displacement [tex]x[/tex]. F represents the force required to create a spring displacement of [tex]x[/tex].

Explanation:

As with many things in physics, the negative sign represents direction. In this case, after a spring is displaced a distance of [tex]x[/tex] from equilibrium, the restoring force created by the spring will be in opposite direction of the force applied to move the spring there, represented by F.

Answer:

It is important because it furnishes information about the composition, the temperature and maybe the mass or relative velocity of the body that emits or absorbs it.

Explanation:

Answer:

Solution given:

velocity=40cm/s

wave length=5cm

we have

frequency =velocity/wavelength=40/5=8hertz.

the frequency of the wave is 8 hertz.

Answer:

can u make the picture less blurry pls

Explanation:

Explanation:

On earth,

g=10 m/s^2

When M=2 kg,

weight on earth=2×10

=20N

When M=3.5 kg,

weight on Earth=3.5×10

=35N

When M=5kg,

weight on Earth=5.25×10

=52.5N