Physics 11th Chap 14 : Topic 14 - Maryam Publications

Physics Chapter 14 : Topic 14

Quark Composition of Protons and Neutrons

1 / 30

According to the Standard Model, protons and neutrons are classified as:

A) Leptons

B) Gauge bosons

C) Baryons

D) Mesons

2 / 30

A proton is composed of which combination of quarks?

A) Three up quarks

B) Two up quarks and one down quark

C) One up quark and two down quarks

D) Three down quarks

3 / 30

The quark composition of a neutron is:

A) $\mathbf{uus}$

B) $\mathbf{uud}$

C) $\mathbf{ddd}$

D) $\mathbf{udd}$

4 / 30

The difference between a proton and neutron is mainly due to:

A) Presence of electrons

B) Difference in atomic size

C) Type and arrangement of quarks

D) Number of quarks

5 / 30

The electric charge of an up quark is:

A) $\mathbf{- \ 1/3\ e}$

B) $\mathbf{+ \ 2/3\ e}$

C) $\mathbf{- \ 1e}$

D) $\mathbf{+ \ 1e}$

6 / 30

The electric charge of a down quark is:

A) $\mathbf{- \ 2/3\ e}$

B) $\mathbf{+ \ 2/3\ e}$

C) $\mathbf{- \ 1/3\ e}$

D) $\mathbf{+ \ 1e}$

7 / 30

The total charge of a proton can be calculated from its quark composition as:

A) $\mathbf{( + \ 2/3) + ( + \ 2/3) + ( + \ 2/3) = + \ 2}$

B) $\mathbf{( + \ 1) + ( - \ 1) + (0) = 0}$

C) $\mathbf{( + \ 2/3) + ( + \ 2/3) + ( - \ 1/3) = + \ 1}$

D) $\mathbf{( + \ 2/3) + ( - \ 1/3) + ( - \ 1/3) = 0}$

8 / 30

The total charge of a neutron is zero because:

A) Its quark charges cancel each other.

B) It contains equal positive and negative electrons.

C) Neutrons contain only neutral quarks.

D) It contains no quarks.

9 / 30

Which combination represents a proton?

A) $\mathbf{udd}$

B) $\mathbf{ddu}$

C) $\mathbf{uud}$

D) All of these

10 / 30

Which combination represents a neutron?

A) $\mathbf{ddd}$

B) $\mathbf{uuu}$

C) $\mathbf{udd}$

D) $\mathbf{uud}$

11 / 30

Quarks inside protons and neutrons are held together by:

A) Weak force only

B) Electromagnetic force

C) Gravitational force

D) Strong nuclear force

12 / 30

Protons and neutrons are called hadrons because they:

A) Are always electrically neutral

B) Are made of quarks and experience strong interaction

C) Are made of electrons

D) Have no mass

13 / 30

Which statement correctly compares proton and neutron composition?

A) Proton has two up quarks, neutron has two down quarks

B) Neutron contains no up quarks

C) Proton has three quarks while neutron has two

D) Both contain identical quarks

14 / 30

If one up quark in a proton changes into a down quark, the particle becomes:

A) A photon

B) Another proton

C) A neutron

D) An electron

15 / 30

The baryon number of a single quark is:

A) $\mathbf{1}$

B) $\mathbf{0}$

C) $\mathbf{1/2}$

D) $\mathbf{1/3}$

16 / 30

The baryon number of a proton is:

A) $\mathbf{0}$

B) $\mathbf{1/3}$

C) $\mathbf{3}$

D) $\mathbf{1}$

17 / 30

Which particle has the same quark composition as a proton but opposite charges?

A) Photon

B) Antiproton

C) Neutron

D) Positron

18 / 30

The quark composition of an antiproton is:

A) $\mathbf{uud}$

B) anti $\mathbf{- \ u}$ anti$\ \mathbf{- \ u}$ anti$\ \mathbf{–\ d}$

C) $\mathbf{udd}$

D) $\mathbf{u}$ anti$\ \mathbf{- \ d}$ anti$\ \mathbf{–\ u}$

19 / 30

Which quark combination gives a neutral baryon?

A) $\mathbf{uuu}$

B) $\mathbf{udd}$

C) $\mathbf{uus}$

D) $\mathbf{uud}$

20 / 30

A proton has charge $\mathbf{+ \ 1e}$ because:

A) It contains one positive electron.

B) Quarks have no charge.

C) The sum of quark charges equals $\mathbf{+ \ 1e}$.

D) It contains only up quarks.

21 / 30

Which statement about quarks is correct?

A) Quarks combine to form particles like protons and neutrons.

B) Quarks are larger than atoms.

C) Quarks carry only positive charge.

D) Quarks can exist freely in normal conditions.

22 / 30

A neutron contains more down quarks than a proton. This causes:

A) Absence of strong force

B) No mass

C) A different electric charge

D) A different quark structure

23 / 30

The mass of a proton mainly comes from:

A) Energy associated with quarks and strong interaction.

B) The masses of electrons inside it.

C) The gravitational force.

D) The neutron inside it.

24 / 30

Which of the following is NOT a baryon?

A) Antiproton

B) Electron

C) Neutron

D) Proton

25 / 30

If the charge of an up quark is $\mathbf{+ \ 2/3\ e}$, then the charge of three up quarks would be:

A) $\mathbf{+ \ 1e}$

B) $\mathbf{0}$

C) $\mathbf{- \ 1e}$

D) $\mathbf{+ \ 2e}$

26 / 30

Which combination represents a particle with charge $\mathbf{+ \ 1e}$?

A) $\mathbf{uud}$

B) $\mathbf{ddd}$

C) $\mathbf{uuu}$

D) $\mathbf{uud}$

27 / 30

Which combination represents a particle with charge $\mathbf{- \ 1e}$?

A) $\mathbf{udd}$

B) $\mathbf{uuu}$

C) $\mathbf{uud}$

D) $\mathbf{ddd}$

28 / 30

Protons and neutrons are not fundamental particles because:

A) They have no mass.

B) They are electrically neutral.

C) They are made of smaller particles called quarks.

D) They do not interact.

29 / 30

Which force allows quarks to remain confined inside protons and neutrons?

A) Weak force

B) Electric force

C) Strong force

D) Gravitational force

30 / 30

The correct quark model of ordinary matter states that:

A) Quarks are made of atoms.

B) All particles contain the same quarks.

C) Protons and neutrons are made of three quarks each.

D) Protons contain electrons and neutrons.

Your score is

0%