Shows are several curves.

Explain with reason, which ones amongest them can be possible trajectories traced by a projectile (neglect air friction).

Due to economic reasons, only the upper sideband of an AM wave is transmitted, but at the receiving station, there is a facility for generating the carrier. Show that if a device is available which can multiply two signals, then it is possible to recover the modulating signal at the receiver station.

A curved surface is shown in the figure. The portion BCD is free of friciton. There are three spherical balls of identical radii and masses. Balls are released from rest one by one from A which is at a slightly greater height than C. With the surface AB, ball 1 has large enough firction to cause rolling down without slipping, ball 2 has a small friction and ball 3 has a negligible frction. Which balls (s) can reach D?

An air chamber of volume V has a neck area of cross section a into which a ball of mass mjust fits and can move up and down without any friction (Fig.14.27). Show that when the ball is pressed down a little and released , it executes SHM. Obtain an expression for the time period of oscillations assuming pressure-volume variations of air to be isothermal [see Fig. 14.27

List the criteria that can act as genetic material must fulfill. Which one of the criteria are best fulfilled by DNA or RNA thus making one of them as better genetic material? Explain.