Horses can run at speeds of 16 meters per second. If a horse running at full

Explain why the life cycle of a star can be compared to the life style of a human

Vladimir79 [104]

A star is born when clouds of dust and elements are gathered together in a certain space due to gravity, more and more mass and therefore pressure builds. When the pressure becomes enough to overcome the electronic repulsive force between two hydrogen nuclei, they are forced together and massive amounts of energy are given off forming helium atoms. This energy is then used to fuse other nuclei together. This could be compared to the way human life starts, where instead of 2 nuclei joining together to start a life cycle, two gametes, or sex cells are joined together. Also at the start of both a star and persons life, we are weak and we gain strength until we reach the height of our existence, then humans slowly become less efficient at doing what they do until eventually they cannot sustain themselves any further.

6 0

2 years ago

A long string is wrapped around a 6.6-cm-diameter cylinder, initially at rest, that is free to rotate on an axle. The string is

lys-0071 [83]

Answer:

$\omega_f=571.42\ rpm$

Explanation:

It is given that,

Diameter of cylinder, d = 6.6 cm

Radius of cylinder, r = 3.3 cm = 0.033 m

Acceleration of the string, $a=1.5\ m/s^2$

Displacement, d = 1.3 m

The angular acceleration is given by :

$\alpha =\dfrac{a}{r}$

$\alpha =\dfrac{1.5}{0.033}$

$\alpha =45.46\ rad/s^2$

The angular displacement is given by :

$\theta=\dfrac{d}{r}$

$\theta=\dfrac{1.3}{0.033}$

$\theta=39.39\ rad$

Using the third equation of rotational kinematics as :

$\omega_f^2-\omega_i^2=2\alpha \theta$

Here, $\omega_i=0$

$\omega_f=\sqrt{2\alpha \theta}$

$\omega_f=\sqrt{2\times 45.46\times 39.39}$

$\omega_f=59.84\ rad/s$

Since, 1 rad/s = 9.54 rpm

So,

$\omega_f=571.42\ rpm$

So, the angular speed of the cylinder is 571.42 rpm. Hence, this is the required solution.

5 0

3 years ago

List the following types of electromagnetic radiation in order of increasing wavelength:(i) the gamma rays produced by a radioac

Naddik [55]

Answer:

In order of increasing wavelength, the answer is:

(i) The gamma rays produced by a radioactive nuclide used in medical imaging

(iv) The yellow light from sodium-vapor streetlights

(v) The red light of a light emitting diode, such as in a calculator display

(ii) Radiation from an FM radio station at 93.1 MHz on the dial

(iii) A radio signal from an AM radio station at 680kHz on the dial

Explanation:

First, you have to know that the wavelength of a sinusoidal wave traveling at a constant speed is given by:

λ $= \frac{v}{f}$

Where λ is the wavelength, $v$ is the constant speed and $f$ is the wave's frequency. In the case of electromagnetic radiation in free space, the constant speed is the speed of light.

From explained above, you can conclude that there is a proportionality relationship between the wavelength and the frequency, they are inversely proportional. That means: the highest frequency will have the shortest wavelength and vice-versa.

So, you have the following types:

(i) The gamma rays produced by a radioactive nuclide used in medical imaging

Frequency : Typically greater than $10^{19}$ Hz

(ii) Radiation from an FM radio station at 93.1 MHz on the dial

Frequency: 93.1 MHz

(iii) A radio signal from an AM radio station at 680 kHz on the dial

Frequency: 680 kHz

(iv) The yellow light from sodium-vapor streetlights

Frequency: Visible spectrum of approx. 508 - 526 THz

(v) The red light of a light-emitting diode, such as in a calculator display

Frequency: Visible spectrum of approx. 400 - 484 THz

Then, you have to organize them from the highest frequency to the smallest one (decreasing frequency), and as the highest frequency will have the shortest wavelength, you are going to have it organized in an increasing wavelength mode.

Then in order of increasing wavelength, the answer will be:

(i) , (iv), (v), (ii), (iii)

3 0

3 years ago

Why is it important for body cell to have twice and many chromosomes as sex cells?

prisoha [69]

Answer:

Why sex cells only need half the number of chromosomes compared to other cells in the body? As gametes are produced, the number of chromosomes must be reduced by half. Why? The zygote must contain genetic information from the mother and from the father, so the gametes must contain half of the chromosomes found in normal body cells.

Explanation:

Brainliest Plzz

8 0

2 years ago

Read 2 more answers

The air in a room has a pressure of 1 atm, a dry-bulb temperature of 24°C, and a wet-bulb temperature of 17°C. Using the psychro

Licemer1 [7]

Answer:

Given that

Dry-bulb temperature(T) =24°C

Wet-bulb temperature(Tw) = 17°C

Pressure ,P = 1 atm

As we know that psychrometric chart are drawn at constant pressure.

From the diagram

ω= specific humidity

Lets take these two lines Dry-bulb temperature(T) line and Wet-bulb temperature(Tw) cut at point P

From chart at point P

a)

Specific humidity,ω = 0.00922 kg/kg

b)

The enthalpy ( h)

h=47.59 KJ/kg

c)

The relative humidity, RH

RH= 49.58 %

d)

Specific volume ,

v= 0.853 m³/kg

5 0

3 years ago