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3 years ago

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A particular X-ray photon has initial energy of 60 keV when it enters the body. This photon transmits through 30 cm of soft tiss

ue and exits the body. Calculate its energy (in keV) after it has exited the body.

1 answer:

ankoles [38]3 years ago

3 0

Answer:

E = 7.334 KeV

Explanation:

given,

initial energy = 60 keV

Δ x = 30 cm

$E = E_0e^{-\mu \Delta x}$

μ(for soft tissue) = 0.7 cm⁻¹ (taken from table)

$E = E_0e^{-0.7\times 20}$

E = 60 × 0.1224

E = 7.334 KeV

energy of x-ray photon after travelling through 30 cm soft tissue in body is E = 7.334 KeV

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Answer:

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Explanation:

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3 years ago

A disk 7.90 cm in radius rotates at a constant rate of 1 190 rev/min about its central axis. (a) Determine its angular speed. 12

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Answer:

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Explanation:

r = Radius of disk = 7.9 cm

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The angular speed is $124.62\ \text{rad/s}$

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Tangential speed at the required point is $3.71\ \text{m/s}$

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The radial acceleration is $1.23\ \text{km/s}^2$ .

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$d=vt\\\Rightarrow d=\omega rt\\\Rightarrow d=124.62\times 7.9\times 10^{-2}\times 2.06\\\Rightarrow d=20.28\ \text{m}$

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A bell is ringing inside of a sealed glass jar that is connected to a vacuum pump. Initially, the jar is filled with air. What d

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Answer:

See Explanation

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(III) A baseball is seen to pass upward by a window with a vertical speed of If the ball was thrown by a person 18 m below on th

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Answer:

<em><u>Assuming that the vertical speed of the ball is 14 m/s</u></em> we found the given values:

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d) t = 4.8 s

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a) <u>Assuming that the vertical speed is 14 m/s</u> (founded in the book) the initial speed of the ball can be calculated as follows:

$V_{f}^{2} = V_{0}^{2} - 2gh$

<u>Where:</u>

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I hope it helps you!

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3 years ago

When catching a baseball, the ball applies a force of 39.6 N to a catcher's glove. If the work done on the catchers glove is 4

cricket20 [7]

Answer:

d = 1.19 m

Explanation:

Given that,

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Work done, W = Fd

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So, it will cover 1.19 m.

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3 years ago