What should be the minimum height of a plane mirror to get full image of an object of 2 m height?

A cannon ball (shell) is fired from a cannon, and it explodes in the mid air. In this regard, which one of the following statements is CORRECT for the cannon ball?

A plane is flying horizontally at 98 m/s and releases an object which reaches the ground in 10 sec. Acceleration due to gravity of the earth is 9.8m/s2. The angle made by the object while hitting the ground is :

Two long parallel wires carry identical electric currents in the same direction. Then they will :

If the temperature of a black body is doubled, then its radiant emittance becomes:

In Young’s double slit experiment, if the separation between the slits is doubled (within the wavelength range), then the fringe width is:

A body of mass 5 kg moving with velocity 2 m/s comes to rest within a distance of 6 m. The work done during the process is:

The quantity of water in one hectare centimeter will be