Straightness and Flatness Test - 2

1. At what distance instrument is placed when straightness is determined with the help of autocollimator?

0.5 to 0.75 mm

0.5 to 0.75 m

0.5 to 0.75 cm

0.5 to 0.75 µm

2. For testing straightness with the help of spirit level, what is the length of each surface section?

Less than spirit level base length

Equal to spirit level base length

Doesn’t depend upon spirit base length

Greater than spirit level base length

3. How the straightness of any surface can be determined with the help of spirit level?

By finding relative angular positions at extreme sections of the surface

By finding relative linear distance at middle of the surface

By finding relative angular positions at any point

By finding relative angular positions at adjacent section

4. For which surfaces, spirit level is used for testing straightness?

Vertical surfaces

Horizontal surfaces

In any plane

Both horizontal and vertical surfaces

5. 1 sec of arc will correspond to how much rise or fall in surface, when surface straightness is tested by autocollimator? (λ is the distance between centres of feet)

0.0006λ

0.00006λ

0.000006λ

0.00006λ

6. Which of the following option is true for autocollimators?
Statement 1: Electronic autocollimator has more resolution than visual autocollimator.
Statement 2: Observations are taken using precision level.

T, T

F, T

F, F

T, F

7. Which of the following is not true for autocollimator?

Contact measurement

Use for small tilts

High sensitivity

Used to determine parallelism

8. Which of the following method is used for the mathematical treatment of determination of straightness with the help of autocollimator?

Taylor’s principle

Bryan method

Least square method

Average method