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3 years ago

15

A student studies how an objects mass and speed are related to its kinetic energy. The table shows the results for one part of t

he investigation.

1 answer:

Bumek [7]3 years ago

4 0

Answer:

I THINK

Explanation:

ITS

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What happens along a stationary front?

oee [108]

Answer: b. The flow of air is neither toward the warm air mass nor toward the cold air mass.

A stationary front forms between two air masses. A stationary front results when the warm front or cold front air stops moving. This occurs due to the fact that warm front and cold front air masses being opposite to each other but neither of them are able to repel the other. This affects the climatic conditions of the region. The weather is often cloudy along a stationary front and also supported with fall of rain and snow especially if the air in the front is cold with low atmospheric pressure.

<em>Therefore, along a stationary front the flow of air is neither toward the warm air mass nor toward the cold air mass. </em>

3 0

3 years ago

Is metallic wire carrying current charged or electrically neutral? Justify. ...?

Vladimir79 [104]

A metallic wire carrying current is not charged - it is electrically neutral.
This is because a wire, or any type of conductor, cannot store charge - the fact that it is carrying current means that charge carriers that already existed in the wire are in motion. There are as many electrons as there are protons in the wire, which makes it neutral - there is no buildup of charge.

7 0

4 years ago

On dry concrete, a car can decelerate at a rate of 7.00 m/s2 , whereas on wet concrete it can decelerate at only 5.00 m/s2 . Fin

MariettaO [177]

Answer:

Explanation:

a ) Let the distance required in former case be d₁ .

initial velocity u = 30 m /s , final velocity v =0 , deceleration a = 7.00 m /s²

v² = u² - 2 a s

0 = 30² - 2 x 7 x d₁

d₁ = 64.28 m

b) initial velocity u = 30 m /s , final velocity v =0 , deceleration a = 5.00 m /s²

v² = u² - 2 a s

0 = 30² - 2 x 5 x d₂

d₂ = 90 m

c)

t = .5 s

s₁ = ut - .5 at²

= 30 x .5 - .5 x 7 x .5²

= 15 - .875

= 14.125 m

t = .5 s

s₂ = ut - .5 at²

= 30 x .5 - .5 x 5 x .5²

= 15 - .625

= 14.375 m

3 0

4 years ago

Para fabricar la bicicleta de un niño pequeño se tiene en cuenta que la fuerza que puede desarrollar es menor que la de un adult

Georgia [21]

Answer:

a) El piñón debe tener 20 dientes.

b) La bicicleta avanza aproximadamente 1,759 metros por cada pedaleada completa.

Explanation:

a) El plato es el engranaje más grande que forma parte del sistema de transmisión, acompañando a la cadena y el piñón integrado a la rueda trasera. Asumiendo que no existen pérdidas por fricción seca y que las condiciones de lubricación del sistema de transmisión son óptimas tal que las pérdidas de potencia son despreciables. Además, supongamos que la bicicleta viaja a velocidad constante, entonces tenemos la siguiente identidad mediante las definiciones de trabajo y potencia:

$T_{P}\cdot \omega_{P} = T_{p}\cdot \omega_{p}$ (1)

Donde:

$T_{P}$ - Torque del plato, en newton-metros.

$T_{p}$ - Torque del piñón, en newton-metros.

$\omega_{p}$ - Rapidez angular del piñón, en radianes por segundo.

$\omega_{P}$ - Rapidez angular del plato, en radianes por segundo.

Sabiendo el hecho que tanto el plato y el piñón experimenta la misma velocidad tangencial, podemos simplificar (1) como sigue:

$\frac{T_{P}}{R_{P}} = \frac{T_{p}}{R_{p}}$ (1b)

Puesto que el radio de cada elemento y el número de dientes son, por separado, directamente proporcionales al número de dientes, modificamos (1b) así y tenemos la siguiente identidad, la cual equivale a su vez a la razón de desarrollo:

$\frac{T_{P}}{T_{p}} = \frac{N_{P}}{N_{p}} = \frac{R_{P}}{R_{p}} = \frac{\omega_{p}}{\omega_{P}}$ (1c)

Donde:

$N_{p}$ - Número de dientes del piñón, sin unidad.

$N_{P}$ - Número de dientes del plato, sin unidad.

Si tenemos que $r = 1,4$ y $N_{P} = 28$ , entonces tenemos que el número de dientes del piñón es:

$r = \frac{N_{P}}{N_{p}}$

$N_{p} = \frac{N_{P}}{r}$

$N_{p} = \frac{28}{1,4}$

$N_{p} = 20$

El piñón debe tener 20 dientes.

b) De acuerdo con la relación de desarrollo, por cada revolución realizada por el plato, el piñón realiza 1,4 revoluciones. Entonces, el avance realizado por la rueda trasera ( $s$ ), en metros, es igual al productor de la relación de desarrollo y la circunferencia de la rueda, es decir:

$s = r\cdot 2\pi\cdot R$ (1)

Donde $R$ es el radio de la rueda trasera, en metros.

Si conocemos que $r = 1,4$ y $R = 0,2\,m$ , entonces el avance realizado por la rueda trasera es:

$s = r\cdot 2\pi\cdot R$

$s = (1,4)\cdot (2\pi)\cdot (0,2\,m)$

$s \approx 1,759 \,m$

La bicicleta avanza aproximadamente 1,759 metros por cada pedaleada completa.

3 0

3 years ago

A stereo speaker is placed between two observers who are 40 m apart, along the line connecting them. if one observer records an

Nadya [2.5K]

The distance from observer A of intensity of sound 59 db is 28.64 m and the distance from observer B of intensity of sound 83 db is 11.36m

Explanation:

Let's solve this problem in parts

let's start by finding the intensity of the sound in each observer

observer A β = 59 db

β = $10 log\frac{I_a}{I_o}$

where I₀ = $1 \times 10^{-12}$ W / m²

$I_a = I_b \times 10 ^{ \frac{\beta}{10} }$

$I_a = 1\times 10 ^{-12} \times 10 ^{ \frac{59}{10} }$

$I_a$ = $2.51 \times 10 ^{-6}$ W / m²

Similarly for Observer b $I_b = 3.16 \times 10 ^ {-4}$

now we use that the emitted power that is constant is the intensity over the area of the sphere where the sound is distributed

P = I A

therefore for the two observers

the area of a sphere is

$A= 4\pi \times r^2$

we substitute the above formula, we get

Let us call the distance from the observer A be to stereo speaker = x, so the distance from the observer B to the stereo speaker = 40- x; we substitute

$I_a (35 -x) ^2 = I_b x^2$

after solving the above equation we get x = 28.64 m

This is the distance of observer A

similarly The distance from observer B is 35 - x

= 40 - 28.64

= 11.36m

To know more about intensity of sound with the given link

#SPJ4

6 0

1 year ago