The surface tension of the alcohol propanol in air has a value of 23.70 units

Proton is placed 100 micrometers from a helium nucleus. Gravity pulls the proton and nucleus together while the electric force p

skad [1K]

Answer:

Electric force is $6.2\cdot 10^{35}$ times stronger than gravitational force

Explanation:

The gravitational force between two objects is given by:

$F_G = G\frac{m_1 m_2}{r^2}$

where

G is the gravitational constant

m1, m2 are the masses of the two objects

r is the separation between the objects

Here we have:

$m_1 = 1.67\cdot 10^{-27}kg$ (mass of the proton)

$m_2=4\cdot 1.67\cdot 10^{-27} =6.68\cdot 10^{-27} kg$ (mass of the helium nucleus is equal to 4 times the mass of a proton)

$r=100 \mu m = 100\cdot 10^{-6} m$

So,

$F_G = (6.67\cdot 10^{-11}) \frac{(1.67\cdot 10^{-27})(6.68\cdot 10^{-27})}{(100\cdot 10^{-6})^2}=7.44\cdot 10^{-56} N$

The electric force between two charged object is given by

$F_E=k\frac{q_1 q_2}{r^2}$

where

k is the Coulomb constant

q1, q2 are the two charges

r is the separation

Here we have

$q_1 = 1.6\cdot 10^{-19}C$ (charge of the proton)

$q_2 = 2\cdot (1.6\cdot 10^{-19})=3.2\cdot 10^{-19}C$ (charge of the helium nucleus is twice that of the proton)

$r=100 \mu m = 100\cdot 10^{-6} m$

So,

$F_E=(9\cdot 10^9) \frac{(1.6\cdot 10^{-19})(3.2\cdot 10^{-19})}{(100\cdot 10^{-6})^2}=4.6\cdot 10^{-20}N$

Therefore, we see that the electric force is much stronger than the gravitational force, by a factor of:

$\frac{F_E}{F_G}=\frac{4.6\cdot 10^{-20}}{7.44\cdot 10^{-56}}=6.2\cdot 10^{35}$

3 0

3 years ago

A laser used for many applications of hard surface dental work emits 2780-nm wavelength pulses of variable energy (0-300 mJ) abo

Bess [88]

Answer:

a

$n = 1.119 *10^{18} \ photons$

b

$P = 1.6 \ W$

Explanation:

From the question we are told that

The wavelength is $\lambda = 2780 nm = 2780 *10^{-9} \ m$

The energy is $E = 80 mJ = 80 *10^{-3} \ J$

This energy is mathematically represented as

$E = \frac{n * h * c }{\lambda }$

Where c is the speed of light with a value $c = 3.0 *10^{8} \ m/s$

h is the Planck's constant with the value $h = 6.626 *10^{-34} \ J \cdot s$

n is the number of pulses

So

$n = \frac{E * \lambda }{h * c }$

substituting values

$n = \frac{80 *10^{-3} * 2780 *10^{-9}}{6.626 *10^{-34} * 3.0 *10^{8} }$

$n = 1.119 *10^{18} \ photons$

Given that the pulses where emitted 20 times in one second then the period of the pulse is

$T = \frac{1}{20}$

$T = 0.05 \ s$

Hence the average power of photons in one 80-mJ pulse during 1 s is mathematically represented as

$P = \frac{E}{T}$

substituting values

$P = \frac{ 80 *10^{-3}}{0.05}$

$P = 1.6 \ W$

6 0

3 years ago

A fisherman notices that his boat is moving up and down periodically without any horizontal motion, owing to waves on the surfac

Paladinen [302]

Answer:

1. λ = 5.60 m , 2. T = 5.80 s 3. v = 0.966 m/s 4. A = 0.315 m

Explanation:

1. The definition of wavelength is the distance between two consecutive maximums or minimums, so that the wave is repeated, in this case they give us the distance between two consecutive maximums, therefore

λ = 5.60 m

2. the period is the time it takes for the wave to start repeating itself, going through the same point. They give time to go from the highest point to the lowest point, which is the time for half a wavelength, so the time for a wavelength is

T = 2 t

T = 2 2.90

T = 5.80 s

3. For all waves the speed is the product of the wavelength by the frequency and the frequency is the inverse of the period

v = λ f

f = 1 / T

v = λ / T

v = 5.60 / 5.80

v = 0.966 m / s

4. The amplitude of the wave is the value of the zero displacement point to the maximum displacement point, give the value between the maximum and minimum displacement

A = d / 2

A = 0.63 / 2

A = 0.315 m

8 0

3 years ago

I NEED HELP PLEASE, THANKS! Light passes from air into water at an angle of 40.0° to the normal. What is the angle of refraction

Vlad [161]

Answer:

Angle of Refraction = 28.9 degrees

Explanation:

We'll use Snell's law for this. It's mathematical form is:

=> $n_1* sin(\alpha _1)=n_2 * sin(\alpha _2)$