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3 years ago

What sound signal alerts others that a boat is backing up?

1 answer:

5 0

"Three short blasts" sound signal alerts others when a boat is backing up based on the boating safety rule. The short blast is a sound which has one second period, thus three short blasts mean three of this kind of sound. The sound signal is used for alerting anything surrounding the boat to avoid a collision.

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Consider a sample of gas in a container on a comfortable spring day in chicago, il. the celsius temperature suddenly doubles, an

Vinil7 [7]

To solve this problem, we must first assume that the gas acts like an ideal gas so that we can use the ideal gas equation:

P V = n R T

where P is the pressure, V is the volume, n is the number of moles, R is the universal gas constant and T is the absolute temperature

Assuming that the number of moles is constant, then we can write all the variables in the left side:

P V / T = k where k is a constant (n times R)

Equating two conditions or two states:

P1 V1 / T1 = P2 V2 / T2

We are given that V2 = 2 V1 therefore

P1 V1 T2 = P2 (2V1) T1

P1 T2 = 2 P2 T1

Additionally we are given that the temperature in Celsius is doubled, however in the formula we use the absolute temperature in Kelvin, therefore:

T1 (K) = T1 + 273.15

T2 (K) = 2T1 + 273.15

and P1 = 12 atm

Substituting:

12 (2T1 + 273.15) = 2 P2 (T1 + 273.15)

P2 = 6 (2T1 + 273.15) / (T1 + 273.15)

Assuming that a nice spring day in Chicago has a temperature of 15 Celsius, therefore:

P2 = 6 (2*15 + 273.15) / (15 + 273.15)

P2 = 6.312 atm

3 0

3 years ago

un avión aterriza en la superficie de un portaaviones a 50 m/s y se detiene por completo en 120 metros, ¿cuál es la aceleración

sergejj [24]

Answer:

La aceleración necesaria para detener el avión es - 10.42 m/s².

Explanation:

Un movimiento uniformemente acelerado (M.U.A) es aquél cuya aceleración es constante y la velocidad de un objeto cambia a medida que el movimiento evoluciona.

Siendo la aceleración "a" el cambio de velocidad al tiempo transcurrido en un punto A a B, la velocidad inicial la velocidad que tiene un cuerpo al iniciar su movimiento en un período de tiempo y la velocidad final la velocidad que tiene un cuerpo al finalizar su movimiento en un período de tiempo, entonces en M.U.A se cumple:

Vf² - Vo² = 2*a*d

donde:

Vf: Velocidad final
Vo: Velocidad inicial
a: Aceleración
d: Distancia recorrida

En este caso:

Vf: 0 m/s, porque el avión se detiene
Vo: 50 m/s
a: ?
d: 120 m

Reemplazando:

(0 m/s)² - (50 m/s)² = 2*a*120 m

Resolviendo:

$a=\frac{(0 m/s)^{2} -(50 m/s)^{2} }{2*120 m}$

a= - 10.42 m/s²

La aceleración necesaria para detener el avión es - 10.42 m/s².

5 0

3 years ago

A balloon rubbed against denim gains a charge of −7.0 µc. what is the electric force between the balloon and the denim when the

zubka84 [21]

The solution for this problem is computed by through this formula, F = kQq / d²Plugging in the given values above, we can now compute for the answer.
F = 8.98755e9N·m²/C² * -(7e-6C)² / (0.03m)² = -489N, the negative sign denotes attraction.

4 0

3 years ago

A police officer at rest at side of highway notices speeder moving at 62 km/h along road.when speeder passes ,officer accelerate

Korolek [52]

To answer the following questions for this specific problem:

a. 11.48 secs

b. Vp = a*t*3.6 = 3*11.48*3.6 = 124.0 km/h

c. 9.1 secs.

I am hoping that this answer has satisfied your query about and it will be able to help you.

4 0

3 years ago

Read 2 more answers

A silver bar 0.125 meter long is subjected to a temperature change from 200 C to 100 C . What will be the length of the bar afte

dimulka [17.4K]

\Delta L= \alpha L_0 (T_f-T_i)

= (18 x 10^-6 /°C)(0.125 m)(100° C - 200 °C)

= -0.00225 m

New length = L + ΔL
= 1.25 m + (-0.00225 m)
= 1.248
So your answer is B.

8 0

4 years ago

Read 2 more answers