Microscopy and Screening Quiz

Play an AI-generated podcast conversation about this lesson

What is the purpose of screening or sieving in the context of particles?

To increase the particle size uniformly

To reduce the particle size to nanometers

To separate particles based on their size ranges (correct)

To mix particles of different sizes together

In industrial screening, what is considered the oversize material?

Particles above the screen aperture size (correct)

Particles smaller than 40 µm

Particles below the screen aperture size

Particles of size below 250 µm

Which type of microscope is more suitable for handling particles as small as 0.005 µm?

Atomic force microscope

Electron microscope (correct)

Scanning microscope

Optical microscope

What happens to particles that pass through a screen in the screening process?

They are segregated into different size ranges Signup and view all the answers

How is industrial screening efficiency typically optimized in terms of material size?

By utilizing screens tailored to specific particle sizes Signup and view all the answers

What does a screen aperture size represent in the context of screening?

Size and shape each particle must pass through Signup and view all the answers

What is the order of open screen area from smallest to largest?

Ao(circle) < Ao(square) < Ao(rectangle) < Ao(slot) Signup and view all the answers

In which zone on the screen surface does particle passage through the screen experience a low velocity?

Zone III Signup and view all the answers

What happens to the rate of particle passage through the screen in Zone II?

It increases Signup and view all the answers

Where does the thickness of material on the screen need to be at an optimum level to achieve maximum screening rate?

Zone II Signup and view all the answers

How does an increase in the rate of feeding affect the thickness of material on the screen at the feed end?

It increases Signup and view all the answers

Why does zone III have a low velocity of particle passage through the screen?

Due to a disorderly movement of particles Signup and view all the answers

What is the purpose of grizzlies in screening operations?

To safeguard primary crushers against overload Signup and view all the answers

In screening operations, what is the role of vibrating screens?

To remove undersize particles Signup and view all the answers

How are most movable screens usually oriented to facilitate flow of feed?

Inclined Signup and view all the answers

Which type of screen is slightly inclined and allows feed material to roll towards the discharge end for screening?

Revolving screens Signup and view all the answers

What is the main benefit of providing periodic motion to screens in screening operations?

To give particles multiple chances to fall through the opening Signup and view all the answers

Which type of screen assembly is powered to shake or vibrate in order to remove oversize material effectively?

Grizzlies Signup and view all the answers