Scientific notation for 7890

Hello<br>what is zenith define it ?

sertanlavr [38]

Answer:

hi,

When one stands at a particular place, the point in the sky directly above the head is called Zenith.

Explanation:

hope it helps(≡^∇^≡)

good day

thank u ✅

4 0

3 years ago

An ice cube at 0c was dropped into 30.0 g of water in a cup at 45.0c. at the instant that all of the ice was melted, the tempera

Ede4ka [16]

The amount of heat given by the water to the block of ice can be calculated by using
$Q=m_w C_{sw} \Delta T_w$
where
$m_w = 30 g$ is the mass of the water
$C_{sw}=4.18 J/(g ^{\circ}C)$ is the specific heat capacity of water
$\Delta T_w = 45.0^{\circ}-19.5^{\circ}C = 20.5^{\circ}C$ is the variation of temperature of the water.

Using these numbers, we find
$Q=(30 g)(4.18 J/(g^{\circ}C))(20.5^{\circ}C)=2571 J$

This is the amount of heat released by the water, but this is exactly equal to the amount of heat absorbed by the ice, used to melt it into water according to the formula:
$Q = m_i L_f$
where $m_i$ is the mass of the ice while $L_f =334 J/g$ is the specific latent heat of fusion of the ice.
Re-arranging this formula and using the heat Q that we found previously, we can calculate the mass of the ice:
$m_i = \frac{Q}{L_f}= \frac{2571 J}{334 J/g} =7.7 g$

3 0

3 years ago

Why does the current is reduced as electrons move through a conductor

hammer [34]

Because the electrons collide with the particles inside the conductor so are therefore slowed down seen as current is the rate of flow of electrons

3 0

3 years ago

If a short-wave radio station broadcasts on a frequency of 9.065 megahertz (MHz), what is the wavelength of

Yakvenalex [24]

Answer:

If the radio wave is on an FM station, these are in Megahertz. A megahertz is one ... Typical radio wave frequencies are about 88~108 MHz .

Explanation:

To calculate the wavelength of a radio wave, you will be using the equation: Speed of a wave = wavelength X frequency.

Since radio waves are electromagnetic waves and travel at 2.997 X

10

8

meters/second, then you will need to know the frequency of the radio wave.

If the radio wave is on an FM station, these are in Megahertz. A megahertz is one million hertz. If the radio wave is from an AM radio station, these are in kilohertz (there are one thousand hertz in a kilohertz). Hertz are waves/second. Hertz is usually the label for the frequency of electromagnetic waves.

To conclude, to determine the wavelength of a radio wave, you take the speed and divide it by the frequency.

Typical radio wave frequencies are about

88

~

108

MHz

. The wavelength is thus typically about

3.41

×

10

9

~

2.78

×

10

9

nm

.

7 0

2 years ago

Define the upper mantle and the lower mantle as well give both the thickness and temperature

defon

Answer:

A

Explanation:

because thats what I put and got it right

8 0

3 years ago