Calipers are precision measuring tools used to measure small lengths on solid objects. There are two main types: engineering calipers and vernier calipers. Engineering calipers have either curved inward jaws for external measurements or curved outward jaws for internal measurements. Vernier calipers have a main scale and a movable vernier scale, allowing for more accurate readings down to 0.01cm. They can measure both external distances using the outside fixed jaw and internal diameters using the inside movable jaw.

1. CALIPERS
By
ARILESERE FATIU .O
Matric Number: 04/25OC013
Department of Science Education (Edu-Tech)
University of Ilorin

2. These are measuring instruments used to
measure smaller length on a solid objects
where the meter rule cannot be used to give
accurate reading or measurement.

3. Types of caliper
 There are two types of calipers
i. engineering calipers and
ii. sliding or vernier caliper.

4. Engineering calipers
 This caliper is also divided into two which are
the
i. external and
ii. internal calipers respectively.
 The external caliper has its jaws curved
inwards and is used to measure external
length on a given solid, While the internal
caliper has its jaws curved outward has they
are shown in fig.1.0 and 1.1 below.

5. External caliper Internal caliper
Object to be
measured d
The
curved
jaw of an
external
caliper The curved jaw of
an internal
caliper
Fig.1.0 Fig.1.1

6. Vernier caliper
This caliper is used to read lengths
accurately than the meter rule. It consists
of a main scale with fixed jaws. On the
caliper there is what we call a moveable
vernier scale which moves on the main
scale, while the outside jaw is made
directly with the main scale as shown
below in fig. 1.2.

7. Venier caliper
Internal jaws
0 1 3 4 5
6 7 8 9
Moveable
vernier
Outside jaws scale

8.  The outside jaw is used to measure
external distance of a solid object, while
the inside jaw is used for such
measurement as the materials diameter.
Vernier caliper can be said to have a
reading accuracy of 0.01cm as its shown
below in fig.1.3(a) and (b).

9. Fig.1.3(a)
3cm 4cm 5cm 6cm 7cm

10. Fig.1.3(b)