A stone is projected vertically upwards with speed '$$v$$'. Another stone of same mass is projected at an angle of $$60^{\circ}$$ with the vertical with the same speed '$$v$$'. The ratio of their potential energies at the highest points of their journey is $$\left[\sin 30^{\circ}=\cos 60^{\circ}=0.5, \cos 30^{\circ}=\sin 60^{\circ}=\frac{\sqrt{3}}{2}\right]$$

An electron (mass $$\mathrm{m}$$ ) is accelerated through a potential difference of '$$V$$' and then it enters in a magnetic field of induction '$$B$$' normal to the lines. The radius of the circular path is ($$\mathrm{e}=$$ electronic charge)

A capacitor, an inductor and an electric bulb are connected in series to an a.c. supply of variable frequency. As the frequency of the supply is increased gradually, then the electric bulb is found to

When both source and listener are approaching each other the observed frequency of sound is given by $$\left(V_L\right.$$ and $$V_S$$ is the velocity of listener and source respectively, $$\mathrm{n}_0=$$ radiated frequency)