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Natasha_Volkova [10]

3 years ago

6

A recent study found that electrons that have energies between 3.45 eV and 19.9 eV can cause breaks in a DNA molecule even thoug

h they do not ionize the molecule. If a single photon were to transfer its energy to a single electron, what range of light wavelengths could cause DNA breaks?minimum wavelength?
maximum wavelength?

1 answer:

vlada-n [284]3 years ago

3 0

Answer:

The Minimum wavelength is $\lambda_{min}= 382.2nm$

The Maximum wavelength is $\lambda_{max}= 624.2nm$

Explanation:

From the question we are told that

The energy range is $E_r = 3.25eV \ and \ 19.9eV$

Considering $E = 19.9eV$

When a single photon is transferred to to an electron the energy obtained can be calculated as follows

$E = 19.9eV = 19.9 *1.6 *10^{-19}J$

This energy is mathematically represented as

$E = \frac{hc}{\lambda_{max}}$

Here h is the Planck's constant with value of $h= 6.625*10^{-34}J\cdot s$

c is the speed of light with value of $c = 3*10^8 m/s$

Substituting values and making $\lambda$ the subject of the formula

$\lambda_{max} = \frac{hc}{E}$

$= \frac{6.625*10^{-34} * 3.0*10^{8}}{19.9*1.6*10^{-19}}$

$\lambda_{max}= 624.2nm$

Considering $E = 3.25eV$

When a single photon is transferred to to an electron the energy obtained can be calculated as follows

$E = 19.9eV = 3.25 *1.6 *10^{-19}J$

This energy is mathematically represented as

$E = \frac{hc}{\lambda_{min}}$

Substituting values and making $\lambda$ the subject of the formula

$\lambda_{min} = \frac{hc}{E}$

$= \frac{6.625*10^{-34} * 3.0*10^{8}}{3.25*1.6*10^{-19}}$

$\lambda_{min}= 382.2nm$

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A small balloon is released at a point 150 feet away from an observer, who is on level ground. If the balloon goes straight up a

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Answer:

$\dfrac{dz}{dt}=0.65\ ft/s$

Explanation:

Given that

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When ,x= 150 ft and y= 14 ft

$z^2=150^2+14^2$

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z=150.74 ft

$z^2=x^2+y^2$

By differentiating with respect to time t

$2z\dfrac{dz}{dt}= 2x\dfrac{dx}{dt}+2y\dfrac{dy}{dt}$

$z\dfrac{dz}{dt}= x\dfrac{dx}{dt}+y\dfrac{dy}{dt}$

Here x is constant that is why

$\dfrac{dx}{dt}=0$

$z\dfrac{dz}{dt}= y\dfrac{dy}{dt}$

Now by putting the values in the above equation we get

$150.74\times \dfrac{dz}{dt}=14\times 7$

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$\dfrac{dz}{dt}=0.65\ ft/s$

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Answer:

The velocity of a ball will be "-70.13 m/s".

Explanation:

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v = ?

As we know,

The equation of motion will be:

⇒ $v^2-u^2=2as$

On substituting the estimated values, we get

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⇒ $v^2=4919.6$

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⇒ $v=70.13 \ m/s$

In downward direction, it will be:

⇒ $v=-70.13 \ m/s$

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