An amplitude-modulated wave is represented by cm (t) = 10[1+0.6 sin(1250t)] sin(103 t). Then the modulation index is:
10
1250
108
0.6
In a hypothetical Bohr hydrogen atom, if the mass of the electron is double then the energy of the electron in the first orbit is:
If A is a square matrix of order 3, then |Adj(Adj A2)| =
Match the following List -I (Complex) List II (Spin only Magnetic Moment)
List -I (Complex) | List II (Spin only Magnetic Moment) | ||
A) | [CoF6]3- | I) | 0 |
B) | [Co(C2O4)3]3- | II) | √24 |
C) | [FeF6]3+ | III) | √8 |
D) | [Mn(CN)6]3- | IV) | √35 |
V) | √15 |
the correct answer is:
If (h,k) is the image of the point (3,4) with respect to the line 2x - 3y -5 = 0 and (l,m) is the foot of the perpendicular from (h,k) on the line 3x + 2y + 12 = 0, then lh + mk + 1 = 2x - 3y - 5 = 0.
If a line ax + 2y = k forms a triangle of area 3 sq.units with the coordinate axis and is perpendicular to the line 2x - 3y + 7 = 0, then the product of all the possible values of k is
Thomson atomic model was proposed by William Thomson in the year 1900. This model explained the description of an inner structure of the atom theoretically. It was strongly supported by Sir Joseph Thomson, who had discovered the electron earlier.
Thomson assumed that an electron is two thousand times lighter than a proton and believed that an atom is made up of thousands of electrons. In this atomic structure model, he considered atoms surrounded by a cloud having positive as well as negative charges. The demonstration of the ionization of air by X-ray was also done by him together with Rutherford. They were the first to demonstrate it. Thomson’s model of an atom is similar to a plum pudding.
Rutherford’s conducted an experiment by bombarding a thin sheet of gold with α-particles and then studied the trajectory of these particles after their interaction with the gold foil.
Bohr model of the atom was proposed by Neil Bohr in 1915. It came into existence with the modification of Rutherford’s model of an atom. Rutherford’s model introduced the nuclear model of an atom, in which he explained that a nucleus (positively charged) is surrounded by negatively charged electrons.