IB IB Physics 3

Question 1

What does Einstein's equation E = mc² express?

Accepted Answer

Mass-energy equivalence

Answer

E = mc² expresses mass-energy equivalence, showing that mass can be converted to energy and vice versa, with c² as the conversion factor.

Question 2

In nuclear physics, what is nuclear fission?

Accepted Answer

The splitting of a heavy nucleus into lighter nuclei

Answer

Nuclear fission is the process where a heavy nucleus (such as uranium-235) splits into two smaller nuclei, releasing a large amount of energy.

Question 3

In the photoelectric effect, what happens when the intensity of light is increased without changing its frequency?

Accepted Answer

The number of emitted electrons increases

Answer

Increasing light intensity increases the number of photons hitting the surface, so more electrons are emitted, but their maximum kinetic energy stays the same.

Question 4

What is absolute zero on the Kelvin temperature scale?

Accepted Answer

0 K

Answer

Absolute zero is 0 K, the theoretical temperature at which particles have minimum thermal energy, equivalent to −273.15 °C.

Question 5

Which gas law states that the pressure of an ideal gas is inversely proportional to its volume at constant temperature?

Accepted Answer

Boyle's Law

Answer

Boyle's Law states P ∝ 1/V at constant temperature, meaning doubling the volume of a gas halves its pressure.

IB - International Baccalaureate Practice Test

IB - International Baccalaureate Practice Test

IB IB Physics 3