In any measurement the significant figures are______________?

A. All accurately known and all doubtful digits
B. Only accurately known digits
C. Only doubtful digits
D. All accurately known digits and the first doubtful digit

A digit zero in a measurement__________________?

A. May be significant may not significant
B. Always significant
C. Always insignificant sign
D. Significant only if left to a significant figure

The uncertainty in a measurement may occur due to_______________?

A. Limitation of an instrument
B. Natural variation of the object to be measured
C. Inadequate technique
D. All given in a, b and c

Pair production cannot take place in a vacuum as ________________?

A. Mass is not conserved
B. Energy is not conserved
C. Momentum is not conserved
D. The chargee is not conserved

Pair production can take place only with_________________?

A. X-rays
B. Gamma rays
C. Uv-rays
D. Ir-rays

A device for producing high-velocity nuclei is ________________?

A. Cloud chamber
B. Linear accelerator
C. A mass spectrograph
D. Wilson cloud chamber

Which of the following will be a better shield against gamma rays ?

A. Ordinary water
B. Heavy water
C. Lead
D. Aluminum

The maximum safe limit dose for persons working in a nuclear power station is ________________?

A. 1 rem per week
B. 5 rem per week
C. 4 rem per week
D. 3 rem per week

Radiations are used for the treatment of skin of a patient is_______________?

A. Alpha rays
B. Gamma rays
C. Beta rays
D. X-rays

Which branch of science plays an important role in the development of technology and engineering ?

A. Chemistry
B. Physics
C. Geology
D. Biology