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3 years ago

List four conditions that may result in the emission of electrons from a conductor

Physics

2 answers:

QveST [7]3 years ago

8 0

There are 4 ways in which electrons are emitted from the conductor.

i. Thermionic emission

ii. Electric field electron emission

iii. Photoelectric emission

iv. Secondary emission

In thermionic emission large amount of external energy in the form of heat is supplied to release free electrons from the metal.

In electric field electron emission, electrons are emitted from the metal surface when the metals are placed in a very strong electric field.

During photoelectric emission, light is absorbed by the metals and this provides energy to the valence electrons which break their bond with the parent atom and which are then released from the atom.

Valence electrons do have some kinetic energy, but they don't have enough energy to escape from the atom. During secondary emission, a high-speed electron is bombarded with an atom, which provides the energy for the valence electrons to break their bonds with their parent atom which are then released from the atom.

NNADVOKAT [17]3 years ago

3 0

Answer:

Conditions that result in the emission of electrons from a conductor:

Heating the conductor to a suitable temperature

Exposing the conductor to a strong light

Subjecting the conductor to a very high applied voltage

Subjecting the conductor to high-speed electrons from another source

Explanation:

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lyudmila [28]

Answer:

Explanation:

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So here we can say that bullet when shot from the rifle then its speed is same as that of convertible in horizontal direction

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3 years ago

A mass of 0.8 kg is fixed at a vertical spring with an unknown spring constant. When spring is released from rest, it extends to

Delicious77 [7]

Answer:

1) k = 52 N/m

2) E = 1.0 J

3) ω = 8.1 rad/s

4) v = 1.4 m/s

Though asked for a velocity, we can only supply magnitude (speed) because we don't have enough information to determine direction.

If it happens to be the first time it is at y = - 10 cm after release, the velocity is upward.

Explanation:

Assuming the initial setup is after all transients are eliminated.

kx = mg

k = mg/x = 0.8(9.8) / 0.15

k = 52.26666.... ≈ 52 N/m

E = ½kA² = ½(52)(0.20²) = 1.045333... ≈ 1.0 J

ω = √(k/m) = √(52 / 0.8) = 8.0829... ≈ 8.1 rad/s

½mv² = ½kA² - ½kx²

v = √(k(A² - x²)/m) = √(52(0.20² - 0.10²)/0.8) = 1.39999... ≈ 1.4 m/s

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3 years ago

An object moves with constant velocity .<br><br> •1st law<br> •2nd law

denis23 [38]

Answer:

An object moves with constant velocity .

Explanation:

•2nd law

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3 years ago

Jackson is designing a new heater, and he wants to experiment with different thermally conductive materials. Which of these mate

Dmitry [639]

Answer:

metal

Explanation:

metal is an excellent conductor for heat and electricity therefore making it perfect to experiment with different temperatures.

7 0

3 years ago

Consider a roller coaster begins 15m above the ground. If the cart has a mass of 75kg, what is the velocity of the cart halfway

SashulF [63]

Answer:

v = 12.12 m/s

Explanation:

Given that,

The mass of the cart, m = 75 kg

The roller coaster begins 15 m above the ground.

We need to find the velocity of the cart halfway to the ground. Let the velocity be v. Using the conservation of energy at this position, h = 15/2 = 7.5 m

$mgh=\dfrac{1}{2}mv^2\\\\v=\sqrt{2gh} \\\\v=\sqrt{2\times 9.8\times 7.5} \\\\v=12.12\ m/s$

So, the velocity of the cart is 12.12 m/s.

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3 years ago