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Witch of the statements about water is true?

alekssr [168]

There are no true statements on the list you posted.

3 0

4 years ago

Need help ASAP

Lerok [7]

Answer:

1. The correct way a cell phone call goes out is;

The phone call goes out, transmits through radio waves, then moves to the central hub. Then the signal go to the nearest tower to the receiver of the call

2. Long wavelength

3. Microwave

Explanation:

1. When making a call through a cell phone, the speech made is digitized such that it is converted to electrical signals which are then converted into number strings that are transmitted out of the antenna of the phone as radio waves which are then picked up by the closest cellphone tower mast which then transmit the signal to the applicable central hub from where the signal is transmitted to the tower closest to the intended call receiver

Therefore, the correct option is that the phone call goes out, transmits through radio waves, then moves to the central hub. Then the signal go to the nearest tower to the receiver of the call

2. The property of AM frequencies that allow them to travel over long distances is long wavelength

The frequency of AM radio waves is between 540 kHz and 1600 kHz, which can be propagated as ground wave or by the ionosphere at night

3. Cell phones makes use of the subcategory of microwave which is the super high frequency (SHF) band which with a range of 3 GHz to 30 GHz

8 0

3 years ago

A calorimeter has aluminum inner cup of mass 120 gram containing 200 ml water at temperature 20 degree Celsius. Brass piece with

dedylja [7]

Answer: Final Temperature= 40.57 deg C; Latent Heat of Fusion of Ice= 80.14 cal/g

Explanation:

The system is said to be isolated to the surroundings. All energy must remain inside the system. We can state that no loss of energy takes place, thus,

5 0

3 years ago

Read 2 more answers

a. What is the peak wavelength for AM0? What temperature T corresponds to this peak wavelength for a blackbody source? Assuming

atroni [7]

Answer:

A) T = 5510 K , B) I = 5,226 10⁷ W / m² , C) I₂ = 1128 W / m²

Explanation:

A) The mass of air is defined as the ratio between the shortest path that sunlight must pass to reach the planet's surface and the length of the beam, is called AM

Am = 1 / cos θ

The AM0 value corresponds to solar radiation in the outer part of the Earth's atmosphere.

The peak of this emission is the peak that emitted from the sun

λ = 526 nm

To find the temperature that corresponds to this emission we use the Wien displacement law

λ T = 2,898 10⁻³

T = 2,898 10⁻³ / 526 10⁻⁹

T = 5510 K

i) The radiance on the surface of the sun is

I = P / A

We can calculate the potency by Stefan's law, for a black body

P = σ A e T⁴

P / A = σ e T⁴

The σ constant is value 5,670 10⁻⁸ W / m²K⁴, we will assume that the Sun emits as a black body, so e = 1

I = sig T⁴

I = 5,670 10⁻⁸ 5510⁴

I = 5,226 10⁷ W / m²

ii) the irradiation at a distance of 1 ua (1,496 1011 m)

Let's use the relationship

P = I A

I₁ A₁ = I₂ A₂

I₂ = I₁ A₁ / A₂

The area of a sphere is

A = 4π R²

Let's replace

I₂ = I₁ (r₁ / r₂)²

Index 1 corresponds to the sun and the index to Earth that is an astronomical unit

r₁ = 6.96 10⁸m (Sun radius)

r₂ = 1,498 1011 m (Earth-Sun distance)

Calculous

I₂ = 5,226 10⁷ (6.96 10⁸ / 1,498 10¹¹)²

I₂ = 1.1281 10³ W / m²

I₂ = 1128 W / m²

8 0

3 years ago

Select all of the statements that are true.

natta225 [31]

The correct statements are "Each orbit holds a fixed number of electrons" and "The n=1 orbit can only hold two electrons." According to the Bohr model, the maximum number of electrons that can occupy an orbit is given by $2n^2$ , where n is the number of the orbit. For instance, when n=1 it means $2n^2= 2(1)^2=2$ . This particular orbit can only hold up to two electrons. Even though the electrons can gain energy and move to higher orbits or electrons from higher orbits can lose energy and drop to the n=1 level, the energy level would not allow more electrons to enter the orbit once it is full. Again the octet rule, which states that atoms achieve stability by having 8 valence electrons, limits the maximum number of electrons that can be occupied by an orbit. The gain and loss of electrons is done to achieve the noble gas configuration and once that is reached no more electron can be added to an orbit

8 0

3 years ago