brodidit for students
ہوم / مشق / ای کیٹ / طبیعیات / مرکزی طبیعیات اور نیم موصل
مرکزی طبیعیات اور نیم موصل
5 سوالات: ای کیٹ طبیعیات، جوابات اور وضاحت کے ساتھ۔
-
The binding energy per nucleon is greatest for nuclei with mass number around:
- 1 4
- 2 56
- 3 120
- 4 238
جواب دیکھیں
درست جواب: 56
Iron-56 and nearby nuclei are the most tightly bound, so fission of heavy nuclei and fusion of light ones release energy.
-
In an n-type semiconductor, the majority charge carriers are:
- 1 Holes
- 2 Electrons
- 3 Protons
- 4 Positrons
جواب دیکھیں
درست جواب: Electrons
Doping with a donor such as phosphorus adds free electrons, which become the majority carriers.
-
When a p-n junction diode is forward biased, the depletion region:
- 1 Widens
- 2 Narrows
- 3 Disappears for good
- 4 Stays unchanged
جواب دیکھیں
درست جواب: Narrows
Forward bias pushes carriers toward the junction, so the depletion region becomes narrow and current flows.
-
An alpha particle consists of:
- 1 Two protons and two neutrons
- 2 One proton and one neutron
- 3 Two electrons
- 4 A single neutron
جواب دیکھیں
درست جواب: Two protons and two neutrons
An alpha particle is the nucleus of a helium-4 atom: two protons and two neutrons.
-
Nuclear fission is the process in which:
- 1 Two light nuclei join to form a heavier nucleus
- 2 A heavy nucleus splits into two lighter nuclei, releasing energy
- 3 An electron leaves the atom
- 4 A nucleus absorbs a photon only
جواب دیکھیں
درست جواب: A heavy nucleus splits into two lighter nuclei, releasing energy
In fission, a heavy nucleus such as uranium-235 splits after absorbing a neutron and releases a large amount of energy.