Q2. Zara travelled in a train moving at an average speed of 120km/h and covered a distance of 40km towards East. Calculate the time taken by the train to cover this distance.

Answer:

[tex]\large \boxed{\text{761 kJ}}[/tex]

Explanation:

You calculate the energy required to break all the bonds in the reactants.

Then you subtract the energy needed to break all the bonds in the products.

                        N₂  +   O₂   ⟶         2NO

                     N≡N  + O=O ⟶       2O-N=O

Bonds:         2N≡N   1O=O        2N-O + 2N=O

D/kJ·mol⁻¹:     941      495           201      607

[tex]\begin{array}{rcl}\Delta H & = & \sum{D_{\text{reactants}}} - \sum{D_{\text{products}}}\\& = & 2 \times 941 +1 \times 495 - (2 \times 201 + 2\times 607)\\&=& 2377 - 1616\\&=&\textbf{761 kJ}\\\end{array}\\\text{The enthalpy of reaction is $\large \boxed{\textbf{761 kJ}}$}.[/tex]

Answer:

25.13 ft

Explanation:

r = 4 feet

ω=0.25 revolution per minute

=1 revolution in  4 minutes  

total number of revolution N = 1 (in 4 minutes )

v=rω

distance traveled = 2×N×π×r

=2×1×π×4  

=8π

= 25.13ft in 4mins

Answer:

Approximately [tex]480\; \rm kPa[/tex], assuming that this gas is an ideal gas.

Explanation:

By Boyle's Law, the pressure of a sealed ideal gas at constant temperature will be inversely proportional to its volume. Assume that this gas is ideal. By this ideal gas law:

[tex]\displaystyle \frac{P(\text{Final})}{P(\text{Initial})} = \frac{V(\text{Initial})}{V(\text{Final})}[/tex].

Note that in Boyle's Law, [tex]P[/tex] is inversely proportional to [tex]V[/tex]. Therefore, on the two sides of this equation, "final" and "initial" are on different sides of the fraction bar.

For this particular question:

Rearrange the equation to obtain:

[tex]\displaystyle P(\text{Final}) = \frac{V(\text{Initial})}{V(\text{Final})} \cdot P(\text{Initial})[/tex].

Before doing any calculation, think whether the pressure of this gas will go up or down. Since the gas is compressed, collisions between its particles and the container will become more frequent. Hence, the pressure of this gas should increase.

[tex]\begin{aligned}P(\text{Final}) &= \frac{V(\text{Initial})}{V(\text{Final})} \cdot P(\text{Initial})\\ &= \frac{1.0\; \rm m^{3}}{0.25\; \rm m^{3}} \times 120\; \rm kPa = 480\; \rm kPa\end{aligned}[/tex].

Answer:

The answer to this should be: 5.0 x 10⁸ Hz

Explanation:

The speed, s, of a wave, equals the product of its frequency, ν, times its wavelength, λ:

s = νλ.

As the question states, the speed of an electromagnetic wave is a constant, c, equal to 3.0 × 10⁸ m/s.

Substituting this constant in the equation for the speed of the wave, you get:

c =  νλ.

From that equation, you can solve for the frequency to show the inverse realation of frequency and wavelength:

ν =  c / λ

Now, you just have to substitute values and compute, leaving you with:

5.0 x 10⁸ Hz

Answer:

[tex]k=784 N/m[/tex]

[tex]\Delta x=8,8 cm[/tex]

Explanation:

Usando la ley de Hook tenemos:

[tex]F=k\Delta x[/tex]

Solving it for k we have:

[tex]k=\frac{F}{\Delta x}[/tex]

[tex]k=\frac{39,2}{0,05}[/tex]

[tex]k=784 N/m[/tex]

Usando la misma ecuación y sabiendo k tenemos:

[tex]\Delta x=\frac{F}{k}[/tex]

[tex]\Delta x=\frac{68,6}{784}[/tex]

[tex]\Delta x=8,8 cm[/tex]

Espero esto te ayude!

Explanation:

To blow up a balloon, start by pinching the neck of the balloon with your index finger and thumb. Then, take a deep breath and put the opening of the balloon in between your lips. When you're ready, loosen your grip on the neck and blow into the balloon opening so the balloon starts to fill with air.May

Answer:

It is not a uniform velocity, because his velocity increases for 5 m every second (acceleration = 5m/s2), meaning his velocity always changes.

When he starts at rest, his velocity is 0 m/s. But in 1 second later, his velocity is already 5m/s. At 2 seconds, his velocity will be 10 m/s.

Answer:

The expansion and contraction of materials can also cause problems. For example, bridges expand in the summer heat and need special joints to stop them bending out of shape.A bimetallic strip has two metal strips glued together. One of these metals expands more for each degree temperature rise than that other.

Answer:

15m/s

Explanation:

500 ÷ 50 = 10m/s

1500 ÷ 75 = 20m/s

10 + 20 = 30

30 ÷ 2 = 15m/s

Answer: 16 miles per second

Explanation:

Find the total distance traveled and the total time.

[tex]\text{average rate}=\dfrac{1500+500}{75+50}=\dfrac{2000\ miles}{125\ second}=\large\boxed{16\ mps}[/tex]

Answer:  25.2 km

Explanation:

3 blocks east and four blocks east = 7 blocks

1 block = 0.3 km  --> 7 blocks = 2.1 km

12 times 2.1 km = 25.2 km

Answer:

C. the blue colour of the Earth's sky

Explanation:

The Pleiades is a cluster of sister stars that are among the closest star cluster to earth.

The reflection nebula of the Pleiades is due to the scattering of the blue light from the hot blue luminous stars that dominate the star cluster. Th blue light is scattered from dust molecules, thought to be predominantly carbon compound like diamond dusts, and other compounds like iron.

The blue colour of the Earth's sky is the closest terrestrial phenomenon to the reflection nebula. On a clear cloudless day, molecules in the air scatter the blue component of light more than the other component colours of white light, giving the sky its characteristic blue coluor.

The common characteristics of the luminous nebula and the Earth's blue sky is that they both have their light scattered by the presence of small particles.

Answer:

Water is non-polar molecule False

Water is polar molecule because the electronegativity of Oxygen is much greater than electronegativity of hydrogen and it has also a bend shape that is why it is polar molecule.

Explanation:

I hope this will help you :)

False. Water is a polar molecule.

Water (H2O) consists of two hydrogen atoms and one oxygen atom. The oxygen atom has a higher electronegativity, meaning it attracts electrons more strongly than hydrogen.

As a result, the shared electrons in the covalent bonds between hydrogen and oxygen are pulled closer to the oxygen atom, creating an uneven distribution of charge.

This leads to a partial negative charge (δ-) on the oxygen atom and partial positive charges (δ+) on the hydrogen atoms, making water a polar molecule.

More on polarity of water can be found here: https://brainly.com/question/30530422

#SPJ6

Answer:

Explanation:

a. CH₄- Covalent bonding(ligação covalente)

b. SrO- ionic bonding (ligação iônica)

c. HBr- Polar Covalent bonding (ligação covalente polar)

d. NH₃ - covalent bonding(ligação covalente)

e. Cl₂O - Covalent bonding (ligação covalente)

f. Li₂O- ionic bonding (ligação iônica)

g. CO₂ - double covalent bonding (ligação covalente dupla)

h. MgCl₂- ionic bonding(ligação iônica)

Answer:

a = 1.07 m/s^2

Explanation:

The computation of the acceleration is shown below:

As we know that

[tex]v_f^{2} - v_i^{2} = 2 ad[/tex]

where,

v_i = 0 m/s  = initial speed

v f = 8 m/s  = final speed

d = 30m = distance

Now placing these values to the above equation

[tex]8^{2} - 0 = 2 \times a \times 30[/tex]

64 = 60a

a = 1.07 m/s^2

We simply applied the above formula so that we could able to determine the acceleration

Answer:

we should not drop a magnet on the floor because the magnets tend to lose magnetism gradually and become weak over a period of time if they are not stored properly.

Answer:

Well depending on the floor like say if it was a wooden floor the magnet might lose it magnetism, if concrete floor the magnetic brake and still lose it magnetism, if a metal floor the magnet would stick not sure if it wood lose it magnetism or not but the possibilities still there, basically what I'm saying is the magnet would lose its magnetism if it were to interact with the floor maybe temporary or maybe permanently.

for those with with a learning disability it's a

Explanation:

Answer:

density=mass/volume

39.943/22.7=1.75

Explanation:

Answer:

[tex]t_{1/2}=6 h[/tex]

Explanation:

Let's use the decay equation.

[tex]A=A_{0}e^{-\lambda t}[/tex]

Where:

We know that [tex]\lambda=\frac{ln(2)}{t_{1/2}}[/tex]

So we have:

[tex]\lambda=\frac{ln(A/A_{0})}{t}[/tex]

[tex]\frac{ln(2)}{t_{1/2}}=\frac{ln(A/A_{0})}{t}[/tex]

[tex]t_{1/2}=\frac{t*ln(2)}{ln(A/A_{0})}[/tex]

[tex]t_{1/2}=6 h[/tex]

Therefore, the half-life of the source is 6 hours.

I hope it helps you!

Answer:

P = VI = (IR)I = I2R

Explanation:

What the equation means is that if you double the current you end up with 4 times the power loss. It's like the area of carpet you need for a room - if you make the room twice as long and twice as wide you need 4x as much carpet. The physical explanation is that the voltage difference along a wire depends on the current - more current flowing with a resistance means more voltage (pressure of electricity if you like) is built up.

This extra voltage means more power. So if you double the current your would double the power, but you also double the voltage which doubles the power again = 4x as much power. P = VI = (IR)I = I2R

I hope this helps you out, if I'm wrong, just tell me.

As I mentioned earlier, Ohm's law gives us the formula P = IV, where V is the voltage ( also known as the electrical potential difference ) and I is the current. It is confusing that P = I²R and P = IV are one in the same - so I want to go a bit deeper on that.

We have three formulas, P = IV, P = I²R, and P = V² / R. Each are considered the same. The two formulas P = I²R, and P = V² / R are derived from the statement that P = IV, under the condition V = IR. Substitute the value of V from this second condition V = IR into P = IV. You would get the following -

P = I( IR ),

P = I²R

That is how one can derive the formula P = I²R, and how P = IV and P = I²R are thought to be one in the same. If you would like, take a look at how to get the formula " P = V² / R, "

V = IR, P = IV

I = V / R, P = IV

P = ( V / R )V,

P = V² / R

Hope that helps!

Answer:

Part A)

Since all of the resistors have equal resistance, hence for finding even only 1 branch It will be fine because current will be the same for all branches.

=> [tex]I = \frac{V}{R_{1} }[/tex]

=> [tex]I = \frac{30}{15}[/tex]

=> I = 2 A

Part B)

Equivalent resistance for parallel circuits is the sum of reciprocals of each resistor.

=> [tex]\frac{1}{R} = \frac{1}{R_{1}}+\frac{1}{R_{2}} +\frac{1}{R_{3}}[/tex]  

=> [tex]\frac{1}{R} = \frac{1}{15}+ \frac{1}{15}+\frac{1}{15}[/tex]

=> [tex]\frac{1}{R} = \frac{3}{15}[/tex]

=> R = 15/3

=> R = 5 ohms

Part C)

I = V/R

Where I is current, V is voltage and R is the equivalent resistance

=> I = 30/5

=> I = 6 A

Answer:

people in urban areas strip the soil of nutrition and makes it difficult to grow crops. people of urban areas consume more energy,food,and water. people in urban areas remove minerals and metals from the ground so, urbanization is a contribution to pollution .

Explanation:

it may help you and give me brainliest

Answer:

pollution and loss of trees not to mention how much electricity we use which doesnt benefit the world.

Explanation: because when we urbanize things we get rid of natural resources around us

Answer:

A  mercury barometer is a device use to measure stomspheric pressure and is constructed as following:

The position of tube creates vacuum between the closed end of the tube and liquid surface and the Mercury has high density that is why used as the liquid to measure pressure.

Answer:

for every action thete is an equal and opposite reaction

Answer:

Newton’s third law of motion says that for every action there is a(n)

equal and opposite reaction.

Explanation:

just got it right edg 1928

Answer:

the following image will make you understand

Explanation:

Answer:

1,600 km

Explanation:

since the acceleration due to gravity reduces by 36%, it means that (1 - 36%) of acceleration still remains:

g' = 64g/100

using the acceleration formula:

g' = g x [R² / (R + height)²]

64g/100 = g x [R² / (R + height)²]

64/100 = R² / (R + height)²

√(64/100) = √[R² / (R + height)²]

8/10 = R / (R + height)

8 (R + height) = 10R

8R + 8height = 10R

8height = 2R

height = 2R / 8 = R / 4

R = 6,400 km

height = 6,400 km / 4 = 1,600 km

Answer:

Answer:

Ted is correct

Explanation:

The equation for gravitational potential energy is PE = m·g·h

The equation for gravitational kinetic energy is KE = 1/2·m·v²

Where:

m = Mass of the object (The racing car)

g = Acceleration due to gravity

h = The height to which the object is raised

v = Velocity of motion of the object

From the principle of conservation of energy, energy can neither be created nor destroyed but changes from one form to another, we have;

Potential energy gained from location at height h = Kinetic energy gained as the object moves down the level ground

m·g·h = 1/2·m·v² canceling like terms gives

g·h = 1/2·v²

v = (√2·g·h)

If the speed is doubled, we have

2·v = 2× (√2·g·h) =  (√2·g·4·h)

Therefore, if 2·v = v₂ then v₂ =  (√2·g·4·h)

Since g, the acceleration due to gravity, is constant, it means that the initial  height must be multiplied or increased 4 times to get the new height, that is we have;

v₂ =  (√2·g·4·h) = (√2·g·h₂)

Where:

4·h = h₂

Which gives;

v₂² = 2·g·h₂

1/2·v₂² = g·h₂

1/2·m·v₂² = m·g·h₂ Just like in the first relation

Therefore, Ted is correct s they need to go up four times the initial height to double the speed.

Explanation:

100 m / (1.20 m) = 83.3

100 m / (0.75 m) = 133.3

Rounded up, the first sprinter takes 84 steps, and the second sprinter takes 134 steps.

Answer:

They're made of silicon and oxygen.

Explanation:

Answer:

circular motion

Explanation:

hope this helps you :)

Answer:

Centripetal motion

Explanation:

As a motorcycle takes a sharp turn the type of motion that occurs is called centripetal motion

Complete Question

The complete question is shown on the first uploaded image

Answer:

The force is  [tex]\= F = (-0.001089, 0 ,0)[/tex]

Explanation:

From the question we are told that

      The magnetic dipole moment of first magnet  is  [tex]z_1 = (6,0,0) A \cdot m^2[/tex]

       The magnetic dipole moment of second magnet  is  [tex]z_2 = (7,0,0) A \cdot m^2[/tex]

       The location of the second magnetic dipole moment is  [tex]x = 0.39 \ m[/tex]

Generally the vector force on the second magnet due to the first is mathematically evaluated as

         [tex]\= F =- \frac{\mu_o }{4 \pi} * \frac{6 * z_1 * z_2}{x^4}[/tex]

Where  [tex]\mu _o[/tex] is the permeability of free space with value  [tex]4\pi * 10^{-7} N/A^2[/tex]

substituting values

            [tex]\= F = - \frac{ 4\pi * 10^{-7} }{4 \pi} * \frac{6 * 6 * 7}{0.39^4}[/tex]

           [tex]\= F = (-0.001089, 0 ,0)[/tex]

Note the negative sign show that the force is an attraction force

Answer:

B

Explanation: