GEAS CHAPTER 1 1

It is the idea that predicts the results of testing based on past experimental data

• Postulate

• Law

• Observation

• Theory

How many zeroes in the measurement 0.00020040 are significant?

• three

• four

• six

• seven

The charge of electron was experimentally discovered by

• Milikan

• Newton

• Einstein

• Chadwick

The idea that electrons revolved in orbits around the nucleus of an atom without radiating energy away from the atom was postulated by:

• Thompson

• Bohr

• Rutherford

• Einstein

The neutrons in an atom:

• Are part of the nuclear charge

• Rotate about the nucleus in elliptical orbits

• Vary in number with different isotopes

• Are always equal in number to the total number of protons

Lenz's law is an example of the law of conservation which one of the following?

• Mass

• Charge

• Momentum

• Energy

Which of the following statement is incorrect?

• Nucleus carries positive charge due to presence of protons in it.

• Entire mass of the atom is concentrated in the nucleus and the mass of electrons is negligible

• Nucleus occupies very small fraction of atom and most of the atom is empty, hence most of the alpha particles passed through the gold foil

• Most of the atom is not empty and hence the alpha particles are deflected back.

What is the charge of a hydrogen atom?

• 1+

• 1-

• 2+

• 0

Quantum theory suggest that

• Emission of energy is continuous

• Energy of radiation is quantized

• Energy is emitted discontinuously in the form of quanta

• Both B and C

The distance between successive orbits while going away from nucleus

• Increases

• Decreases

• Decreases then increases

• Remains the same