All categories

3 years ago

What is quantum physics?

Physics

1 answer:

lara [203]3 years ago

5 0

Answer:

A fundamental theory that provides a description of the physical properties of nature at the scale of atoms and subatomic particles.

Explanation:

You might be interested in

Dr. John Paul Stapp was U.S. Air Force officer who studied the effects of extreme deceleration on the human body. On December 10

Mars2501 [29]

Answer:

a) $a=5.7551 \times g$

b) $d=20.5539\times g$

Explanation:

Given:

speed of rocket initially, $v_i=0\ m.s^{-1}$

top speed of rocket after acceleration, $v=282\ m.s^{-1}$

time taken to get to the top speed, $t_i=5\ m.s^{-1}$

final speed of the rocket, $v_f=0\ m.s^{-1}$

time taken to get to the final speed after reaching the top speed, $t_f=1.4\ s$

Now the acceleration:

$a=\frac{v-v_i}{t_i}$

$a=\frac{282-0}{5}$

$a=56.4\ m.s^{-2}$

Now as a fraction of gravity:

$a=\frac{56.4}{9.8}\times g$

$a=5.7551 \times g$

Now, the deceleration:

$d=\frac{0-282}{1.4}$

$d=201.4285\ m.s^{-2}$

Now as a fraction of gravity:

$d=\frac{201.4285}{9.8}\times g$

$d=20.5539\times g$

6 0

4 years ago

An electron is projected with an initial speed vi = 4.60 × 105 m/s directly toward a very distant proton that is at rest. Becaus

frutty [35]

Answer:

$2.99\times 10^{-19}\ m$

Explanation:

<u>Given:</u>

$u$ = initial velocity of the electron = $4.60\times 10^5\ m/s$

$v$ = final velocity of the electron = $3u$

$x$ = initial position of the electron from the proton = very distant = $\infty$

<u>Assume:</u>

$m$ = mass of an electron = $9.1\times10^{-31}\ kg$

$e$ = magnitude of charge on an electron = $1.6\times10^{-19}\ C$

$p$ = magnitude of charge on an proton = $1.6\times10^{-19}\ C$

$k$ = Boltzmann constant = $9\times 10^9\ Nm^2/C^2$

$y$ = final position of the electron from the proton

$\Delta K$ = change in kinetic energy of the electron

$W$ = work done by the electrostatic force

$F$ = electrostatic force

$r$ = instantaneous distance of the electron from the proton

Let us first calculate the work done by the electrostatic force.

$W=\int Fdr\\\Rightarrow W = \int \dfrac{kep}{r^2}dr\\\Rightarrow W = kep\int \dfrac{1}{r^2}dr\\\Rightarrow W = kep\left | \dfrac{1}{r} \right |_{y}^{x}\\\Rightarrow W = kep\left ( \dfrac{1}{x}-\dfrac{1}{y} \right )\\\Rightarrow W = kep\left ( \dfrac{1}{x}-\dfrac{1}{\infty} \right )\\\Rightarrow W =\dfrac{kep}{x}$

Using the principle of the work-energy theorem,

As only the electrostatic force is assumed to act between the two charges, the kinetic energy change of the electron will be equal to the work done by the electrostatic force on the electron due to proton.

$\therefore \Delta K = W\\\Rightarrow \dfrac{1}{2}m(v^2-u^2)= \dfrac{kep}{x}\\\Rightarrow \dfrac{1}{2}m((3u)^2-u^2)= \dfrac{kep}{x}\\\Rightarrow \dfrac{1}{2}m(8u^2)= \dfrac{kep}{x}\\\Rightarrow x= \dfrac{2kep}{8mu^2}\\\Rightarrow x= \dfrac{2\times 9\times 10^9\times 1.6\times10^{-19}\times 1.6\times10^{-19}}{8\times 9.1\times10^{-31}\times (4.60\times 10^5)^2}\\\Rightarrow x=2.99\times 10^{-10}\ m\leq$

Hence, the electron is at a distance of $2.99\times 10^{-10}\ m$ when the electron instantaneously has speed of three times the initial speed.

8 0

4 years ago

Two objects are rubbed together, creating friction.

just olya [345]

The answer is B electrons will be rubbed from one surface to another

6 0

4 years ago

Read 2 more answers

Unpolarized light is incident upon two polarization filters that do not have their transmission axes aligned. If 21% of the ligh

Debora [2.8K]

Answer:

49.6°

Explanation:

$I_0$ = Unpolarized light

$I_2$ = Light after passing though second filter = $0.21I_0$

Polarized light passing through first filter

$I_1=\frac{I_0}{2}$

Polarized light passing through second filter

$I_2=\frac{I_0}{2}cos^2\theta\\\Rightarrow 0.21I_0=\frac{I_0}{2}cos^2\theta\\\Rightarrow cos^2\theta=\frac{0.21I_0}{\frac{I_0}{2}}\\\Rightarrow cos\theta=\sqrt{\frac{0.21I_0}{\frac{I_0}{2}}}\\\Rightarrow \theta=cos^{-1}\sqrt{\frac{0.21I_0}{\frac{I_0}{2}}}\\\Rightarrow \theta=cos^{-1}\sqrt{0.21\times 2}\\\Rightarrow \theta=cos^{-1}\sqrt{0.42}\\\Rightarrow \theta=49.6^{\circ}$

The angle between the two filters is 49.6°

5 0

4 years ago

What kind of substance has particles that are close together but can change shape depending on its container?

zloy xaker [14]

I'm pretty sure that is a liquid

6 0

3 years ago

Read 2 more answers

What is quantum physics? ​

What is quantum physics?