Quiz 1

The number of protons in an element is its

• atomic weight

• atomic number

• relative atomic mass

• mass number

When a substance undergoes beta decay

• The atomic number increases by 1

• 
  The atomic number decreases by 2

• The atomic number does not change

• The atomic number decreases by 3

If the half life of Uranium-240 was 10 years, how long would it take for it to decay from 310g to 80g?

• 10 years

• 240 years

• 20 years

• 30 years

The rate at which a radioactive element decays is its ____.

• quarter life

• whole life

• wonderful life 

• half life

An isotope of an element has the same number of _________, but a different number of _________.

• Protons, electrons

• Protons, neutrons

• Electrons, neutrons

• Neutrons, protons

According to special theory of relativity, mass of an object moving relative to an observer with a velocity comparable to the velocity of light.

• Increases

• Decreases

• Remain constant

• None of the above

Time interval between two events as recorder by an observer in relative motion with velocity comparable to velocity of light with respect to the point of occurrence of the event.

• Dilated

• Shortens

• Remains constant

• None of the above

The S.I unit of plank’s constant is

• Joule per sec

• Joule per sec²

• Joule – sec

• Joule per sec³