A 1 m long metal rod AB completes the circuit as shown in figure. The area of circuit is perpendicular to the magnetic field of 0.10 T. If the resistance of the total circuit is 2 \(\Omega\) then the force needed to move the rod towards right with constant speed (v) of 1.5 m/s is _____ N.
The figure shows a pipe with cross-section area 10 \( cm^2 \). Water flows from one end with velocity 20 cm/s. The other end of the pipe is closed and consists of 10 holes each of area 30 \( mm^2 \). Find the velocity of water coming out from each hole: 

The figure shows a disc of mass \( m \) and radius \( R \) hinged at point 'A' on its periphery and free to oscillate about the axis. Find the time period for small oscillations of the disc: 
Identify the total number of surfaces in the given 3D object. 