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\(^{-10}\)m
4.10 x 10\(^{-10}\)m
3.90 x 10\(^{-10}\)m
5.50 x 10\(^{-14}\)m
Correct answer is D
de broglie wavelength formula in terms of kinetic energy:
λ = \(\frac{h}{\sqrt{2mE}}\)
λ = \(\frac{6.6 *10^{-34}}{\sqrt{2 *9.1*10^{-31} *100 }}\)
λ = 5.50 x 10\(^{-14}\)m
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]
One major reason why electrical appliances in homes are normally earthed is that the-----------
person touching the appliance is safe from electric shock
appliances are maintained at a higher p.d. than the earth
appliances are maintained at a lower p.d. than the earth
appliances are maintained at the same p.d. with that of the earth
Correct answer is A
Earthing of an electrical appliance meant the outer metallic case of appliance is connected with earth, wire which is welded to the end of a copper rod and it is burned in the ground. It save the appliance during short-circuiting by passing Excessive current to earth