Question

When an object is placed between the jaws of a vernier caliper, the zero of the vernier scale is found to be on the right of $7^{th}$the division of the main scale. The $8^{th}$division of the vernier scale is found to coincide with one of the divisions of the main scale. Arrange the following steps in sequential order to determine the length of the object. [$1MSD=1mm,numberofVSD=10$]

(A) Determine the length of the object
(B) Use the formula $MSR+(VSR\times LC)$
(C) Note the M.S.R., V.C.D., 1 M.S.D, and number of V.S.D.
(D) By using the information given determine the least count.

• A. ACBD
• B. CDBA
• C. DBCA
• D. ACDB

Answer 1

The correct option is B

CDBA

Step 1:Given data

$1MSD=1mm$

Number of VSD=$10$

the zero of the vernier scale is found to be on the right of $7^{th}$the division of the main scale so,

So, the main scale reading is $7mm$

The $8^{th}$division of the vernier scale is found to coincide with one of the divisions of the main scale

So, the varnier scale reading VSR=$8$

Step 2: Calculations

The least count of the vernier caliper is defined as the least value that can be measured by the device.

Least count LC=$\frac{smallestnumberonmainscale}{totalnumberofdivitiononvernierscale}=\frac{1}{10}=0.1mm$

Now, the total reading on length can be measured using the equation,

$$\begin{gathered} Totalreading=MSR+(VSR\times LC) \\ TR=7+(8\times 0.1) \\ TR=7+0.8 \\ TR=7.8mm \end{gathered}$$

the value of length is 7.8 mm

So, the sequential order to calculate length should be,

(C) Note the M.S.R., V.C.D., 1 M.S.D, and number of V.S.D

(D) By using the information given determine the least count.

(B) Use the formula $MSR+(VSR\times LC)$

(A) Determine the length of the object

Hence, Option (b) is correct.