A baseband signal of 3.5 MHz frequency is modulated with a carrier signal of 3.5 GHz frequency using amplitude modulation method. What should be the minimum size of antenna required to transmit the modulated signal?

A speech signal given by 11 sin(2200 $$\pi$$t) V is used for amplitude modulation with a carrier signal given by 44 sin(6600 $$\pi$$t) V. The minimum amplitude of modulated wave will be :

In AM modulation, a signal is modulated on a carrier wave such that maximum and minimum amplitudes are found to be 6 V and 2 V respectively. The modulation index is :

A radio can tune to any station in $$6\mathrm{MHz}$$ to $$10\mathrm{MHz}$$ band. The value of corresponding wavelength bandwidth will be :

The maximum and minimum voltage of an amplitude modulated signal are $$60\mathrm{V}$$ and $$20\mathrm{V}$$ respectively. The percentage modulation index will be :

At a particular station, the TV transmission tower has a height of 100 m. To triple its coverage range, height of the tower should be increased to

A square wave of the modulating signal is shown in the figure. The carrier wave is given by $$C(t)=5\sin (8\pi t)$$ Volt. The modulation index is :

In the case of amplitude modulation to avoid distortion the modulation index $$(\mu )$$ should be :

A FM Broadcast transmitter, using modulating signal of frequency 20 kHz has a deviation ratio of 10. The Bandwidth required for transmission is :

Find the modulation index of an AM wave having $$8\mathrm{V}$$ variation where maximum amplitude of the AM wave is $$9\mathrm{V}$$.

The activity of a radioactive material is 2.56 $$\times$$ 10$$-$$3 Ci. If the half life of the material is 5 days, after how many days the activity will become 2 $$\times$$ 10$$-$$5 Ci ?

In the following nuclear reaction, $$D\text{buildrel}\alpha \frac{⟶}{D_1}\text{buildrel}{\beta }^{-}\frac{⟶}{D_2}\text{buildrel}\alpha \frac{⟶}{D_3}\text{buildrel}\gamma \frac{⟶}{D_4}$$ Mass number of D is 182 and atomic number is 74. Mass number and atomic number of D4 respectively will be _________.

Following statements related to radioactivity are given below : (A) Radioactivity is a random and spontaneous process and is dependent on physical and chemical conditions. (B) The number of un-decayed nuclei in the radioactive sample decays exponentially with time. (C) Slope of the graph of loge (no. of undecayed nuclei) Vs. time represents the reciprocal of mean life time ($$\tau$$). (D) Product of decay constant ($$\lambda$$) and half-life time (T1/2) is not constant. Choose the most appropriate answer from the options given below :

The Q-value of a nuclear reaction and kinetic energy of the projectile particle, Kp are related as :

Given below are two statements : Statement I : In hydrogen atom, the frequency of radiation emitted when an electron jumps from lower energy orbit (E1) to higher energy orbit (E2), is given as hf = E1 $$-$$ E2 Statement II : The jumping of electron from higher energy orbit (E2) to lower energy orbit (E1) is associated with frequency of radiation given as f = (E2 $$-$$ E1)/h This condition is Bohr's frequency condition. In the light of the above statements, choose the correct answer from the options given below :

A hydrogen atom in its ground state absorbs 10.2 eV of energy. The angular momentum of electron of the hydrogen atom will increase by the value of : (Given, Planck's constant = 6.6 $$\times$$ 10$$-$$34 Js).

How many alpha and beta particles are emitted when Uranium 92U238 decays to lead 82Pb206 ?

A radioactive nucleus can decay by two different processes. Half-life for the first process is 3.0 hours while it is 4.5 hours for the second process. The effective half-life of the nucleus will be:

Which of the following figure represents the variation of {l_n}\left( {{R \over {{R_0}}}} \right) with $$l_{n}A$$ (if R = radius of a nucleus and A = its mass number)

The ratio for the speed of the electron in the 3rd orbit of He+ to the speed of the electron in the 3rd orbit of hydrogen atom will be :