Question

1. Which instrument is used to compare the masses of
objects?
(A) a balance
(B) a barometer
(C) a manometer
(D) a measuring cylinder

2. How many significant figures in 3.9400 x 106
(A) 5
(B) 6
(C) 7
(D) 8

3. Which of the following is derived quantity?
(A) Mass
(B)Length
(E) Velocity
(D) Time​

Answer 1

1)...(A) a balance

2)...(B) 6

3) ..b) lenght

Answer 2

The correct answer to the following question is given below

1. The instrument used to compare the masses of objects is a balance. It is used to measure the mass of the object, by weighing the difference of mass or weight. It is used to measure the weight of the object. The correct option is (a).
2. Significant figures in 3.9400 × 106 are 5. The value of 3.9400×106 is 417.64. Significance refers to the accuracy with which you know the value. So, the significant value is 5 for 417.64. The correct option is (a).
3. Velocity is the derived quantity. Derived quantity is the physical quantity that is obtained by the combination of two physical quantities either by multiplication or division. The correct option is (e).