Ask question

Ask question

All categories

3 years ago

13

Which of the following objects works by burning fuel to push hot air toward the ground and create thrust to use in lifting off?

a. rocket c. space station b. space probe call

2 answers:

Zigmanuir [339]3 years ago

7 0

The answer is "all", as all three operate in that manner :)

Elena L [17]3 years ago

5 0

the answer is all above you are welcome

You might be interested in

Refraction occurs when light passing from one medium to another. True or False

kodGreya [7K]

Answer: True

Refraction is a phenomenon in which the light bends or changes its direction (and changes the speed of propagation, as well) <u>when passing through a medium</u> with a refractive index $n$ <u>different from the other medium. </u>

Where the Refractive index is a number that describes how fast light propagates through a medium or material:

$n=\frac{c}{v}$

Being $n$ a relation between the speed of light in vacuum $c$ and its speed in the other medium $v$ .

It is important to note that in this process, the wavelength may be modified because it depends on the medium, however, the refracted ray of light does not change its frequency.

7 0

4 years ago

A tank of gasoline (n = 1.40) is open to the air (n = 1.00). A thin film of liquid floats on the gasoline and has a refractive i

klio [65]

Answer:

1.08

Explanation:

This is the case of interference in thin films in which interference bands are formed due to constructive interference of two reflected light waves , one from upper layer and the other from lower layer . If t be the thickness and μ be the refractive index then

path difference created will be 2μ t.

For light coming from rarer to denser medium , a phase change of π occurs additionally after reflection from denser medium, here, two times, once from upper layer and then from the lower layer , so for constructive interference

path diff = nλ , for minimum t , n =1

path diff = λ

2μ t. = λ

μ = λ / 2t

= 626 / 2 x 290

= 1.08

5 0

3 years ago

Mike roller skates with a constant speed of 10 miles per hour. How long will he take to travel a distance of 15 miles.

dsp73

(Didulfykxgxgjlztppxcjcud hcjffifufydhcjvjfudusxjcjcuv

7 0

3 years ago

In the simple Bohr model of the eighth excited state of the hydrogen atom, the electron travels in a circular orbit around a fix

Ksju [112]

Answer:

Net force on electron will be $12.568\times 10^{-12}N$

Explanation:

We have given that the orbit $r=4.28\times 10^{-9}m$

Speed of the electron $v=2.43\times 10^5m/sec$

Mass of the electron is given as $m=9.11\times 10^{-31}kg$

Centripetal acceleration is given by $a_c=\frac{v^2}{r}=\frac{(2.43\times 10^5)^2}{4.28\times 10^{-9}}=1.3796\times 10^{19}m/sec^2$

Force is given by F = ma

So force $F=9.11\times 10^{-31}\times 1.3796\times 10^{19}=12.568\times 10^{-12}N$

8 0

3 years ago

The magnetic field in a plane monochromatic electromagnetic wave with wavelength λ = 598 nm, propagating in a vacuum in the z-di

Oksanka [162]

Answer:

For this given plane monochromatic electromagnetic wave with wavelength λ=598 nm, the wavenumber is $k=0,0105\ x\ 10^{-9}\ m^{-1}$ .

Explanation:

For a plane electromagnetic wave we have that the electrical and magnetic field are:

$E(r,t)=E_{0}\ cos ( wt-kr)\\\ B(r,t)=B_{0}\ cos(wt-kr)$

In this case we have the data for the magnetic field. We are told that the magnetic field in a plane electromagnetic wave with wavelength λ=598 nm, propagating in a vacuum in the z direction ( $\hat k$ ) is described by

$B=8.7\ x\ 10^{-6}\ T sin(kz-wt) (\hat i+\hat j)$

( $\hat i,\hat j, \hat k$ are the unit vectors in the x,y,z directions respectively)

The wavenumber k is a measure of the spatial frequency of the wave, is defined as the number of radians per unit distance:

$k=\frac{2\pi}{\lambda}$

where λ is the wavelength

So we get that

$k=\frac{2\pi}{\lambda} \rightarrow k=\frac{2\pi}{598 nm} \rightarrow k=0,0105\ x\ 10^{9}\ m^{-1}$

The wavenumber is

$k=0,0105\ x\ 10^{9}\ m^{-1}$ .

4 0

3 years ago