Please help me if you can.
I can't figure out how the answer for number 30 is C and 31 is C. My question is how did they get that answer?

Answer:

22

Explanation:

bc it just is

Answer:

it depends on the medium :D

Answer: NO.

Explanation: Oxygen is not a compound. It has only one element in it.

Answer:

[tex]5.2\ \text{m/s}[/tex]

[tex]70^{\circ}[/tex] south of east

Explanation:

[tex]v_a[/tex] = 3 m/s

[tex]\theta_a[/tex] = [tex]20^{\circ}[/tex] north of east

[tex]v_b[/tex] = 6 m/s

[tex]\theta_b[/tex] = [tex]40^{\circ}[/tex] south of east = [tex]360-40=320^{\circ}[/tex] north of east

x and y component of [tex]v_a[/tex]

[tex]v_{ax}=v_a\cos \theta\\\Rightarrow v_{ax}=3\times \cos 20^{\circ}\\\Rightarrow v_{ax}=2.82\ \text{m/s}[/tex]

[tex]v_{ay}=v_a\sin\theta\\\Rightarrow v_{ay}=3\times \sin20^{\circ}\\\Rightarrow v_{ay}=1.03\ \text{m/s}[/tex]

x and y component of [tex]v_b[/tex]

[tex]v_{bx}=v_b\cos \theta\\\Rightarrow v_{bx}=6\times \cos 320^{\circ}\\\Rightarrow v_{bx}=4.6\ \text{m/s}[/tex]

[tex]v_{by}=v_b\sin\theta\\\Rightarrow v_{by}=6\times \sin320^{\circ}\\\Rightarrow v_{by}=-3.86\ \text{m/s}[/tex]

[tex]\Delta v=v_b-v_a\\\Rightarrow \Delta v=(4.6-2.82)\hat{i}+(-3.86-1.03)\hat{j}\\\Rightarrow \Delta v=1.78\hat[i}-4.89\hat{j}[/tex]

Magnitude

[tex]|\Delta v|=\sqrt{(-4.89)^2+1.78^2}\\\Rightarrow \Delta v=5.2\ \text{m/s}[/tex]

Direction

[tex]\theta=\tan{-1}|\dfrac{-4.89}{1.78}|\\\Rightarrow \theta=70^{\circ}[/tex]

The magnitude of the change in velocity vector is [tex]5.2\ \text{m/s}[/tex] and the direction is [tex]70^{\circ}[/tex] south of east.

The change in velocity will be  [tex]\Delta V=5.2\ \frac{m}{s}[/tex] and the direction will be [tex]70^o[/tex] South to east.

Any quantity which is defined by its magnitude and direction both are called as the vector quantities.

Now the data given in the question will be given as:

[tex]V_a[/tex] = 3 m/s

[tex]\theta[/tex] = [tex]20^o[/tex] north of east

[tex]V_b[/tex] = 6 m/s

[tex]\theta[/tex] =  [tex]40^o[/tex]south of east =  360-40=320 north of east

Now we will find the x and y component of [tex]V_a[/tex]

[tex]V_{ax}=V_acos\theta[/tex]

[tex]V_{ax}=3\times Cos20[/tex]

[tex]V_{ax}=2.82\ \frac{m}{s}[/tex]

[tex]V_{ay}=V_aSin\theta[/tex]

[tex]V_{ay}=3\times Sin20[/tex]

[tex]V_{ay}=1.03\ \frac{m}{s}[/tex]

Now we will find the x and y component of [tex]V_b[/tex]

[tex]V_{bx}=V_bcos\theta[/tex]

[tex]V_{bx}=6\times cos\320[/tex]

[tex]V_{bx}=4.6\ \frac{m}{s}[/tex]

[tex]V_{by}=V_bSin\theta[/tex]

[tex]V_{by}=6\times Sin320[/tex]

[tex]V_{by}=-3.86\ \frac{m}{s}[/tex]

Now change in velocity will be

[tex]\Delta V=V_b-V_a[/tex]

[tex]\Delta V=(4.6-2.82)i+(-3.86-1.03)j[/tex]

[tex]\Delta V=1.78i-4.89j[/tex]

The magnitude can be find out as follows:

[tex]\Delta V=\sqrt{(-4.89^2+(1.78^2)}[/tex]

[tex]\Delta V=5.2\ \frac{m}{s}[/tex]

The direction of the vector will be

[tex]\theta= tan^{-1}(\dfrac{-4.89}{1.78})[/tex]

[tex]\theta=70^o[/tex]

Thus the change in velocity will be  [tex]\Delta V=5.2\ \frac{m}{s}[/tex] and the direction will be [tex]70^o[/tex] South to east.

To know more about Vectors follow

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Answer:

so we don't drown and die.

Explanation:

Answer:

Potential energy is related to mass and height. More context is required otherwise the answer here is an equation with several unknowns. PE = mgL(1 – COS θ) where θ is the angle away from the vertical and L is the length of the string.

Explanation:

Answer:

3. converging lens

Explanation:

When the rays of light coming parallel to principle axis after refraction through the lens passes through a point called focus, since it converge all the ray at one point, that is why it is said to be converging lens.

Answer & Explanation:

In science, rationality and creativity work together. Creativity allows us to view and solve problems with innovation and openness. Scientific theories often came from sparks of creative thinking and bold yet logical processes.

Answer:

Explanation:

This is a missile throwing exercise, let's find the distance

         x = v₀ₓ / t

         t = v₀ₓ / x

let's calculate

         t = 2.5 / 12

         t = 0.2083 s

as time is a scalar this is the same value for descends to the ground

         y = v_{oy} t  - 1/2 g t²    

we calculate

         v_y = 0 - 9.8 0,2083  

         v_y = - 2.04 m / s

the negative sign indicates that the speed is down

A pumpkin is thrown horizontally off of a building at a speed of 2.5 m/s and travels a horizontal distance of 12 m before hitting the ground. We can ignore air resistance.

What is the pumpkin's vertical velocity when it hits the ground?

Answer: -47.04

Answer:

because u feel pain and u get shaky and fall

Explanation:

Answer:

Explanation:because it hurts so you fall

Answer:

25 seconds

Explanation:

500/20

chemical reaction for fossil fuels:combustion of fuels.

Difference between biomass and fossil fuels:how much carbon dioxide is produced

Comparing biomass with other renewable energy sources:does not have as much energy potential as fossil fuels.

Making energy choices locally: biomass

Answer:

F=mv^2/r = 50x(900)/625 = 72N

The centripetal force of 180 N is acting on the girl who is in the roller coaster ride with a speed of 30 m/s in a horizontal circle with a radius of 25m.

A centripetal force is the force which makes a body follow a circular path. Here, the direction is always orthogonal to the motion of body and towards a fixed point of instantaneous center of curvature of path.

The centripetal force acting on an object in circular path can be calculated with the help of a formula:

F = mv²/r

where, F = centripetal force acting on the object,

m = mass of the object,

v = velocity of the object,

r = radius of the circular path.

By putting the given values into the formula, we get:

F = [50 × (30)²]/25

F = [50 × 900]/25

F = 4500/25

F = 180 N

Therefore, the centripetal force acting on the girl is 180 N.

Learn more about Centripetal force here:

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Answer: B

Explanation: I can tell the block weights more since the water went down

Answer:

13,308 MAYBE IF IT ISN'T IM SO SORRY

Explanation:

Answer:

[tex]Pressure = 29723.1\ N/m^2[/tex]

Explanation:

Given

[tex]Force = 8694N[/tex]

[tex]Length = 0.45m[/tex]

[tex]Width = 0.65m[/tex]

Required

The force exerted on the floor by the box

First, calculate the area covered by the box (i.e. the base area)

[tex]Base\ Area = Length * Width[/tex]

[tex]Base\ Area = 0.45m * 0.65m[/tex]

[tex]Base\ Area = 0.2925m^2[/tex]

Pressure is calculated as:

[tex]Pressure = \frac{Force}{Area}[/tex]

[tex]Pressure = \frac{8694N}{0.2925m^2}[/tex]

[tex]Pressure = 29723.0769231\ N/m^2[/tex]

[tex]Pressure = 29723.1\ N/m^2[/tex] --- approximated

Answer:

carpet

Explanation:

Diffuse reflection is the reflection of light from a surface such that an incident ray is reflected at many angles rather than at just one angle as in the case of specular reflection.

The structure of carpet's surface is as shown. Thus it shows large amount of diffuse reflection.

Answer:

El mango llega al suelo a una velocidad de 329.982 metros por segundo.

Explanation:

El mango experimenta un movimiento de caída libre, es decir, un movimiento uniformemente acelerado debido a la gravedad terrestre, despreciando los efectos de la viscosidad del aire y la rotación planetaria. Entonces, la velocidad final del mango, es decir, la velocidad con la que llega al suelo, se puede determinar mediante la siguiente fórmula cinemática:

[tex]v = v_{o}+g\cdot t[/tex] (1)

Donde:

[tex]v_{o}[/tex] - Velocidad inicial, en metros por segundo.

[tex]v[/tex] - Velocidad final, en metros por segundo.

[tex]g[/tex] - Aceleración gravitacional, en metros por segundo al cuadrado.

[tex]t[/tex] - Tiempo, en segundos.

Si sabemos que [tex]v_{o} = -75\,\frac{m}{s}[/tex], [tex]g = -9.807\,\frac{m}{s^{2}}[/tex] y [tex]t = 26\,s[/tex], entonces la velocidad final del mango es:

[tex]v = v_{o}+g\cdot t[/tex]

[tex]v = -75\,\frac{m}{s}+\left(-9.807\,\frac{m}{s} \right)\cdot (26\,s)[/tex]

[tex]v = -329.982\,\frac{m}{s}[/tex]

El mango llega al suelo a una velocidad de 329.982 metros por segundo.

Answer:

Prefer Soil more than sand

Explanation:

Answer: 4276.2 calories

Explanation:

Given

mass of steam is 6 gm at [tex]100^{\circ}C[/tex]

Conversion of steam to ice involves

Calories released during the conversion of steam to water at [tex]100^{\circ}C[/tex]

[tex]E_1=mL_v\quad [L_v=\text{latent heat of vaporisation}]\\E_1=6\times 533=3198\ cal.[/tex]

Calories released during the conversion of water at [tex]100^{\circ}C[/tex] to water at [tex]0^{\circ}C[/tex]

[tex]E_2=mc(\Delta T)\quad [c=\text{specific heat of water,}1\ cal./gm.^{\circ}C]\\E_2=6\times 1\times 100=600\ cal.[/tex]

Calories released during the conversion of water to the ice at [tex]0^{\circ}C[/tex]

[tex]E_3=mL_f\quad [L_f=\text{latent heat of fusion}]\\E_3=6\times 79.7=478.2\ cal.[/tex]

The total energy released is

[tex]E=E_1+E_2+E_3\\E=3198+600+478.2=4276.2\ cal.[/tex]

Answer:

The answer is B - the bending of rock layers happens due to stress, and this process is called folding. Faults are when it looks broken/displaced

Answer:

the correct one is 2

Explanation:

The emission and arcion spectra are similar, in the emission spectra a heated material emits photons for the internal transitions of the electrons, in the absorption spectrum the continuous emission of a lamp is absorbed at the energies that the material has transitions.

In our case the material is low early, so all the electrons are in their base states.

As the light beam has all wavelengths, those corresponding to the first emission of the material will be observed.

When reviewing the answers, the correct one is 2

Answer:

[tex]fe = \frac{9 \times 10 {}^{9} \times 1.6 \times 10 {}^{ - 19} \times 1.6 \times 10 { - 19}^{?} }{(1 \times 10 { }^{ - 8}) {}^{2} } \\ fe = 23.04 \times 10 {}^{ - 13} n[/tex]

Answer:

Because the two genes depend on each other, it is possible for someone to actually be a carrier of a dominant trait like brown eyes.  And if two blue eyed parents are carriers, then they can have a brown eyed child.  Genetics is much bkj

Explanation:

So all you light eyed parents with dark eyed kids, stop asking those paternity questions (unless you have other reasons to be suspicious).  Darker eyed kids are a real possibility that can now be explained with real genes.  

Answer:

Se obtienen 2,27 gramos de metanol.

Explanation:

La reacción entre monóxido de carbono e hidrógeno para producir metanol es la siguiente:

CO + 2H₂ → CH₃OH  

Para encontrar el reactivo limitante y el reactivo en exceso, debemos calcular el número de moles de CO y H₂:

[tex]\eta_{CO} = \frac{m}{M} [/tex]              

En donde:    

m: es la masa

M: es el peso molecular  

[tex]\eta_{CO} = \frac{m}{M_{CO}} = \frac{2,0 g}{28,01 g/mol} = 0,071 moles [/tex]

[tex]\eta_{H_{2}} = \frac{2,0 g}{2,02 g/mol} = 0,99 moles [/tex]

Dado que la relación estequiométrica entre CO y H₂ es 1:2, el número de moles de hidrógeno gaseoso que reaccionan con el monóxido de carbono es:

[tex] \eta_{H_{2}} = \frac{2}{1}*0,071 = 0,142 moles [/tex]      

Entonces, se necesitan 0,142 moles de H₂ para reaccionar con 0,071 moles de CO y debido a que se tienen más moles de H₂ (0,99 moles) entonces el reactivo limitante es CO y el reactivo en exceso es H₂.

Ahora podemos encontar la masa de metanol obtenida usando el reactivo limitante (CO) y sabiendo que la realcion estequiométrica entre CO y CH₃OH es 1:1.    

[tex] \eta_{CH_{3}OH} = \eta_{CO} = 0,071 moles [/tex]

[tex] m = 0,071 moles*32,04 g/mol = 2,27 g [/tex]

Por lo tanto, se obtienen 2,27 gramos de metanol.

Espero que te sea de utilidad!      

Answer:

B. A hill 70ft tall.

Explanation:

Answer:

Δx is the path difference between the two waves.

...

Phase Difference And Path Difference Equation.

Formula Unit

Phase Difference \Delta \phi=\frac{2\pi\Delta x}{\lambda } Radian or degree

Path Difference \Delta x=\frac{\lambda }{2\pi }\Delta \phi meter

Answer:

7.35..kg

Explanation:

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