# Engineering Metrology Questions and Answers – Measure an Internal Taper in Blind Hole

This set of Engineering Metrology MCQs focuses on “Measure an Internal Taper in Blind Hole”.

1. Which of the following is used to measure an internal taper in a blind hole?
a) One pin
b) Two balls
c) Single ball
d) Two pins

Explanation: For this method of measurement of internal taper of blind holes, generally two steel balls are used. These balls are generally made up of steel.

2. Which of the following is the first step in the method of measuring an internal taper in a blind hole?
a) Balls are placed in bottom of the taper
b) All the balls are placed over the support
c) Pins are placed in bottom of the tape
d) All the pins are placed over the support

Explanation: In the method of measurement of internal taper of blind hole the first step is that the two balls which are of equal diameter are placed in the bottom. Each ball is placed in bottom corner of the internal taper of blind hole.

3. Which of the following is used to fill the gap between the balls?
a) Combination of pins
b) Combination of balls
c) Slip gauges
d) Plug gauges

Explanation: In this method, after placing the balls the gap between the balls is filled with the combination of the slip gauges. The length of slip gauges between the balls should be noted very carefully.

4. Which of the following is the blind hole?
a) All ordinary holes are called blind holes
b) Those hole which has specified depth without breaking through the other side
c) Those holes which goes all the way through metal
d) Clearance holes are the blind holes

Explanation: Blind holes are those which are drilled or reamed etc. at a specified depth. It is drilled without breaking through the other side. Those holes which go all the way through the work piece are known as through holes.

5. How the error in angle measurement can be decreased when the internal taper of the blind hole is measured?
a) Increase the height of slip gauge combination
b) Decrease the height of slip gauge combination
c) In place of balls, pins are used
d) Balls of different diameter are used

Explanation: When the internal taper of blind hole is measured by using balls then the error in the angle measurement of taper can be decreased by choosing the height of slip gauge combination as large as possible.

6. Which of the following is true for the measurement of internal taper in the blind hole?
a) Roller of large radius should be used
b) No effect of roller size
c) Roller of small radius should be used
d) Both the rollers are of different size

Explanation: In this method of measurement of internal taper, the radius of rollers should be small so that the contact between the flanks of sloping sides and rollers is made in a plane which is near to the base.

7. What is the formula for the internal tapered angle of blind hole?
a) Sin A/2 = (l1-l2)/2h
b) Cot A/2 = (l1-l2)/2h
c) Cos A/2 = (l1-l2)/2h
d) Tan A/2 = (l1-l2)/2h

Explanation: Tan A/2 = (l1-l2)/2h or A = 2 tan -1(l1-l2)/2h is the formula to measure the internal tapered angle of the blind hole where (l1-l2) is the different in length of slip gauges and h is the height of slip gauges upon which balls are placed.

8. Which of the following is used as a support in the blind hole when the internal taper is measured by using balls?
a) Wooden block
b) Slip gauges
c) Balls of larger diameter
d) Internal taper itself acts as a support

Explanation: A combination of slip gauges of height let ‘h’ is prepared and placed in the hole as support. Now, place the two balls in the upper position. Each ball touched the tapered side of the hole and space is filled with another combination of slip gauges.

Sanfoundry Global Education & Learning Series – Engineering Metrology.