Page 40 - Physics - XI

Q3. What is the number of signifi cant digits in the edge length of a cube measured with the
given Vernier Calliper?
a. 1 b. 2 c. 3 d. 4

Q4. What is the volume of a cube with the correct number of signifi cant digits?
a. 1.03 cm b. 1.0303 cm c. 1.03 mm d. 1.0303 mm 3
3
3
3
Answer key
1. (a), 2. (b), 3. (c), 4. (a)

Assertion-Reason Type Questions

These consist of two statements– Assertion (A) and Reason (R). Answer these questions by selecting
the appropriate option given below:

a. Both A and R are true and R is the correct explanation of A.
b. Both A and R are true and R is not the correct explanation of A.
c. A is true but R is false.

d. A is false but R is true.
1. Assertion(A) : A Vernier Calliper has a positive error of 0.5 mm, then the correction is – 0.5 mm.

Reason(R) : In the case of positive zero error, the measured length is greater than the actual
length.
2. Assertion(A) : The precision of a measurement does not depend on the least count of the
measuring instrument.
Reason(R ) : The smaller the least count, greater is the number of signifi cant fi gures in
measurement value.
3. Assertion(A) : The accuracy of a standard screw gauge is more than the accuracy of a standard
Vernier Calliper.

Reason(R) : The least count of a standard screw gauge is more than the least count of a
standard Vernier Calliper.
4. Assertion(A) : A screw gauge having a smaller value of pitch has greater accuracy.

Reason(R) : The least count of a screw gauge is directly proportional to the number of
divisions on the circular scale.
5. Assertion(A) : In Searle's experiment, it is better to start the experiment with some initial load
on the hanger.
Reason(R) : In Searle's experiment, it is desirable that the wire is straight and no kinks are
there.

Answer key
1. (a), 2. (d), 3. (c), 4. (c), 5. (b)

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