Which subatomic particle can be absent from an atom?

A long, straight wire is surrounded by a hollow metal cylinder whose axis coincides with that of the wire. The wire has a charge

Alexxx [7]

Explanation:

It is given that, a long, straight wire is surrounded by a hollow metal cylinder whose axis coincides with that of the wire.

The charge per unit length of the wire is $\lambda$ and the net charge per unit length is $2 \lambda$ .

We know that there exist zero electric field inside the metal cylinder.

(a) Using Gauss's law to find the charge per unit length on the inner and outer surfaces of the cylinder. Let $\lambda_i\ and\ \lambda_o$ are the charge per unit length on the inner and outer surfaces of the cylinder.

For inner surface,

$\phi=\dfrac{q_{enclosed}}{\epsilon_o}$

$E.A=\dfrac{q_{enclosed}}{\epsilon_o}$

$0=\dfrac{\lambda_i+\lambda}{\epsilon_o}$

$\lambda_i=-\lambda$

For outer surface,

$\lambda_i+\lambda_o=2\lambda$

$-\lambda+\lambda_o=2\lambda$

$\lambda_o=3\lambda$

(b) Let E is the electric field outside the cylinder, a distance r from the axis. It is given by :

$E_o=\dfrac{\lambda_o}{2\pi \epsilon_o r}$

$E_o=\dfrac{3\lambda}{2\pi \epsilon_o r}$

Hence, this is the required solution.

6 0

3 years ago

Dos cargas iguales de 10^-7C estan separadas por una distancia de 2m. calcule la fuerza con que se repelen

m_a_m_a [10]

Answer:

$F=2.25\times 10^{-5}\ N$

Explanation:

According to question,

Charge 1 and charge 2 are $10^{-7}\ C$

The distance between charges is 2 m

We need to find the force with which two positive charges repel. It is called electrostatic force of repulsion. It can be given by :

$F=\dfrac{kq^2}{r^2}\\\\F=\dfrac{9\times 10^9\times (10^{-7})^2}{2^2}\\\\F=2.25\times 10^{-5}\ N$

So, the electric force of repulsion is $2.25\times 10^{-5}\ N$ .

8 0

3 years ago

You have 1.2kg of (AU)gold (that's quite a bit of money at $1839/ounce). Using a heat source you apply 3096 J to the gold and re

melamori03 [73]

Answer:

129 J/Kg°C

Explanation:

Given :

Mass of gold, m = 1.2kg

Quantity of heat applied, Q = 3096 J

Temperature, t2 = 40°C

Temperature, t1 = 20°C

Change in temperature, dt = (40-20)°C = 20°C

Using the relation :

Q = mcdt

Where, C = specific heat capacity of gold

3096 = 1.2kg * C * 20°C

3096 J = 24kg°C * C

C = 3096 J / 24 kg°C

C = 129 J/Kg°C

7 0

3 years ago

A car goes from 0 to 26.8 m/s in 6.2 s. What is the average acceleration of the car?

Nutka1998 [239]

Answer:

0 - 60 mph = 0 - 26.8 m/s = 0 - 96.6 km/h; 0 - 100 km/h = 0 - 27.8 m/s = 0 - 62.1 mph.

Explanation:

5 0

3 years ago

Identify the person who made the correct statement.

dmitriy555 [2]

The answer is: [C]: Neither Juan nor Christina are correct.
_________________________________________________
Explanation:
_____________
Consider Juan's statement:
_______________________
"Juan said fossils deposits always contain only one type of organism."
__________________________
This statement is incorrect. There are many instances of fossil deposits containing more than one type of organism.
___________________________________
Consider Christina's statement.
___________________________________
"Christina said fossil deposits never contain one type of organism."
___________________________________________
This statement is incorrect. Fossil deposits, by definition (of "fossil") ALWAYS contain <u>at least one type</u> of organism.
___________________________________________
As such, neither Juan nor Christina are correct.
And as such, Answer choice: [C] is the correct answer.
_____________________
Answer choices A, B, and D are ruled out.

7 0

3 years ago