Physics Questions and Answers
If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.
If you want to learn more about the nature and properties of matter and energy or you're simply preparing for a Physics exam, these Physics past questions and answers are ideal for you.
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Correct answer is C
No explanation has been provided for this answer.
high velocity electrons are abruptly stopped in metals
energy changes occur within the nuclei of atoms
energy changes occur within the electronic structure of atoms
electrons are deflected in very strong magnetic fields
Correct answer is B
Gamma rays are produced in the disintegration of radioactive atomic nuclei and in the decay of certain subatomic particles.
Gamma radiation is emitted by excited nuclei or other processes involving subatomic particles;
it often accompanies alpha or beta radiation, as a nucleus emitting those particles may be left in an excited (higher-energy) state.
1.22 x 10−10m
4.10 x 10−10m
3.90 x 10−10m
5.50 x 10−14m
Correct answer is D
de broglie wavelength formula in terms of kinetic energy:
λ = h√2mE
λ = 6.6∗10−34√2∗9.1∗10−31∗100
λ = 5.50 x 10−14m
Arrange the following radiations in order of increasing ionization of air.
I. Alpha
Il. Gamma
IIl. Beta
I < III < II
II < I < III
II < III < I
I < II
Correct answer is C
Alpha particles are highly ionising because of their double positive charge, large mass (compared to a beta particle) and because they are relatively slow.
They can cause multiple ionisations within a very small distance.
And the gamma radiation has the least ionising power.
In doping an intrinsic semiconductor to produce a p-type semiconductor,
the semiconductor is heated up
a donor element is added
an acceptor element is added
the semiconductor is conducted to a battery
Correct answer is C
If the dominant impurity atoms are ACCEPTOR type in the semiconductor, it will have a majority of holes over the electrons [p-type]