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3 years ago

Why is it not necessary for radio telescope surfaces to be as smooth as a mirror?

1 answer:

8 0

It doesn't on account of radio waves are longer than optical waves. Radio waves are a sort of electromagnetic radiation with wavelengths in the electromagnetic range longer than infrared light. These long waves are in the radio locale of the electromagnetic range.

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An electron is accelerated within a particle accelerator using a 100 MV electric potential. The 100 MeV electron moves along an

Delicious77 [7]

Answer:

The length of the tube is 3.92 m.

Explanation:

Given that,

Electric potential = 100 MV

Length = 4 m

Energy = 100 MeV

We need to calculate the value of $\gamma$

Using formula of relativistic energy

$E=m_{0}c^2(\dfrac{1}{\sqrt{1-\dfrac{v^2}{c^2}}}-1)$

Put the value into the formula

$1.6\times10^{-15}= 9.1\times`10^{-31}\times9\times10^{16}(\dfrac{1}{\sqrt{1-\dfrac{v^2}{c^2}}}-1)$

$(\dfrac{1}{\sqrt{1-\dfrac{v^2}{c^2}}}-1)=\dfrac{1.6\times10^{-15}}{9.1\times10^{-31}\times9\times10^{16}}$

Here, $\gamma-1=(\dfrac{1}{\sqrt{1-\dfrac{v^2}{c^2}}}-1)$

$\gamma-1=0.01953$

$\gamma=0.01953+1$

$\gamma=1.01953$

We need to calculate the length

Using formula of length

$L'=\dfrac{L}{\gamma}$

Put the value into the formula

$L'=\dfrac{4}{1.01953}$

$L'=3.92\ m$

Hence, The length of the tube is 3.92 m.

8 0

3 years ago

An engineering firm is designing a ski lift. The wire rope needs to travel with a linear velocity of 2.0 meters per second, and

Mazyrski [523]

Answer:

The diameter of the bull-wheel is 3.82

Explanation:

Given that,

Velocity = 2.0 m/s

Angular velocity = 10 rev/m

$\omega=10\times\dfrac{2\pi}{60}$

$\omega=1.0472\ rad/s$

We need to calculate the diameter of bull-wheel

Using formula of angular velocity

$v= r\omega$

$r=\dfrac{v}{\omega}$

Put the value into the formula

$r=\dfrac{2.0}{1.0472}$

$r=1.91\ m$

The diameter of the bull-wheel

$D=2r$

$D=2\times1.91$

$D=3.82\ m$

Hence, The diameter of the bull-wheel is 3.82 m.

6 0

3 years ago

A horizontal applied force of magnitude 25 N acts on a block sliding on a horizontal surface. The force of friction between the

kompoz [17]

' A ' and ' D ' are both correct statements.

3 0

3 years ago

A ray of light has a wavelength of

MArishka [77]

Answer:

The wavelength in vacuum is equal to 428.8 nm.

Explanation:

Given that,

The wavelength of light, $\lambda=284\ nm$

The refractive index of glass, n = 1.51

We need to find the wavelength in vacuum. The relation between wavelength and refractive index is given by :

$n=\dfrac{\lambda_v}{\lambda}\\\\\lambda_v=n\times \lambda\\\\\lambda_v=1.51\times 284\\\\\lambda_v=428.8\ nm$

So, the wavelength in vacuum is equal to 428.8 nm.

6 0

3 years ago

A 50.0-kg block is being pulled up a 16.0Â° slope by a force of 250 n that is parallel to the slope. the coefficient of kinetic

Drupady [299]

When dealing with multiple forces acting on a body, it is advisable to draw a free-body diagram like that shown in the picture. There are four forces acting on the box: weight (W) pointing straight down, normal force perpendicular to the slope denoted as Fn, force used to push the box upwards along the slope and the frictional force acting opposite to the direction of motion of the box denoted as Ff. Frictional force is equal to coefficient of kinetic friction (μk) multiplied with Fn.

∑Fy = Fn - mgcos30° = 0
Fn = (50)(9.81)(cos 16) = 471.5 N

When in motion, the net force is equal to mass times acceleration according to Newton's 2nd Law of Motion:

Fnet = F - μk*Fn - mgsin30° = ma
250 - (0.2)(471.5 N) - (50)(sin 16°) = (50)(a)
a = 2.84 m/s²

8 0

3 years ago