In an amplitude modulation, a modulating signal having amplitude of X Volt is superimposed with a carrier signal of amplitude Y Volt in first case. Then, in second case, the same modulating signal is superimposed with different carrier signal of amplitude 2Y Volt. The ratio of modulation index in the two cases respectively will be :

Which of the following frequencies does not belong to FM broadcast ?

Given below are two statements :

Statement I : For transmitting a signal, size of antenna ( $l$ ) should be comparable to wavelength of signal (at least $l=\frac{\lambda}{4}$ in dimension)

Statement II: In amplitude modulation, amplitude of carrier wave remains constant (unchanged).

In the light of the above statements, choose the most appropriate answer from the options given below

The amplitude of $$15 \sin (1000 \pi \mathrm{t})$$ is modulated by $$10 \sin (4 \pi \mathrm{t})$$ signal. The amplitude modulated signal contains frequency (ies) of

A. $$500 \mathrm{~Hz}$$

B. $$2 \mathrm{~Hz}$$

C. $$250 \mathrm{~Hz}$$

D. $$498 \mathrm{~Hz}$$

E. $$502 \mathrm{~Hz}$$

Choose the correct answer from the options given below: