The number 0.00243<br> has how many significant digits

How many excess electrons must be present on each sphere if the magnitude of the force of repulsion between them is 3.33Ã—Ã—10âˆ

AlekseyPX

Answer:

There are 756.25 electrons present on each sphere.

Explanation:

Given that,

The force of repression between electrons, $F=3.33\times 10^{-21}\ N$

Let the distance between charges, d = 0.2 m

The electric force of repulsion between the electrons is given by :

$F=k\dfrac{q^2}{r^2}$

$q=\sqrt{\dfrac{Fr^2}{k}}$

$q=\sqrt{\dfrac{3.33\times 10^{-21}\times (0.2)^2}{9\times 10^9}}$

$q=1.21\times 10^{-16}\ C$

Let n are the number of excess electrons present on each sphere. It can be calculated using quantization of charges. It is given by :

q = ne

$n=\dfrac{q}{e}$

$n=\dfrac{1.21\times 10^{-16}}{1.6\times 10^{-19}}$

n = 756.25 electrons

So, there are 756.25 electrons present on each sphere. Hence, this is the required solution.

8 0

3 years ago

A photon with an energy E = 2.12 GeV creates a proton-antiproton pair in which the proton has a kinetic energy of 96.0 MeV. What

Oksanka [162]

Answer:

The kinetic energy of the anti proton is 147.4 MeV.

Explanation:

Given that,

Energy = 2.12 GeV

Kinetic energy = 96.0 MeV

We need to calculate the kinetic energy of the anti proton

Using formula of energy

$E_{photon}=m_{p}c^2+m_{np}c^2+K.E_{p}+K.E_{np}$

We know that,

$m_{p}c^2=m_{np}c^2$

So, $E_{photon}=2mc^2+K.E_{p}+K.E_{np}$

$K.E_{np}=E_{photon}-(2mc^2+K.E_{p})$

Put the value into the formula

$K.E_{np}=2.12\times10^{9}-2\times938.3\times10^{6}-96\times10^{6}$

$K.E_{np}=147.4\ MeV$

Hence, The kinetic energy of the anti proton is 147.4 MeV.

6 0

2 years ago

An object starts at 4m/s and accelerates to 6m/s in 10 seconds. Find its displacement.

Natalka [10]

Answer:

Explanation:

The 2 equations we need here are, first:

$a=\frac{v_f-v_0}{t}$ and then once we solve for the acceleration here:

$v^2=v_0^2+2a$ Δx

Solving for acceleration:

$a=\frac{6-4}{10}=\frac{1}{5}\frac{m}{s^2}$ and now we will use that in the other equation:

$6^2=4^2+2(\frac{1}{5})$ Δx and

36 = 16 + $\frac{2}{5}$ Δx and

20 = $\frac{2}{5}$ Δx and

$\frac{5}{2}(20)=$ Δx so

Δx = 50 m

6 0

2 years ago

Human activities can have an impact on natural disasters.

kolezko [41]

I think you wanted to know whether the statement in question is true or false. Assuming this fact, i am answering the question and hope that it helps you. It is a true fact that human activities can have an impact on natural disasters. The increase in global temperature due to emission of greenhouse gases can cause the sea level to rise and create hurricanes.

6 0

3 years ago

Read 2 more answers

The vertical normal stress increase caused by a point load of 10 kN acting on the ground surface at a point 1m vertically below

Tomtit [17]

Answer:

(b) 4.775 kN

Explanation:

see the attached file

8 0

2 years ago

The number 0.00243 has how many significant digits