A metre long narrow bore held horizontally (and closed at one end) contains a 76 cm long mercury thread, which traps a 15 cm column of air. What happens if the tube is held vertically with the open end at the bottom ?

Air is trapped in a horizontal glass tube by 36 cm mercury column as shown below : If the tube is held vertical keeping the open end up, lengh of air column shrink to 19 cm. What is the lengh (in cm) by which the mercury column shifts down?

The two parallel circular loops of wire shown in fig each have a radius R = 20 cm and are separated by a distance a = 0.5 cm. The bottom loop is held fixed and the top loop hangs from one end of the arm of an equal arm balance. Since a is much smaller than R, the magnetic field produced by one loop at the other is practically the same as if both were long straight wires. if the curret in each loop is 20 A, how big is the force of attraction of one loop for the other?

The two parallel circular loops of wire shown in fig each have a radius R = 20 cm and are separated by a distance a = 0.5 cm. The bottom loop is held fixed and the top loop hangs from one end of the arm of an equal arm balance. Since a is much smaller than R, the magnetic field produced by one loop at the other is practically the same as if both were long straight wires. if the current in each loop is 20 A. How much additional mass m must be added to the right-hand pan of the balance to keep the loops separated by 0.5 cm, when the currents are turned on?

One end of a long string of linear mass density 8.0 xx 10^-3 kg m^-1 is connected to an electrically driven tuning fork of frequency 256 Hz. The other end passes over a pulley and is tied to a pan containing a mass of 90 kg. The pulley end absorbs all the incoming energy so that reflected waves at this end have negligible amplitude. At t= 0, the left end (fork end) of the string x = 0 has zero transverse displacement (y = 0) and is moving along positive y-direction. The amplitude of the wave is 5.0 cm. Write down the transverse displacement y asfunction of x and tthat describes the wave on the string

A child sits stationary at one end of a long trolley moving uniformly with a speed V on a smooth horizontal floor. If the child gets up and runs about on the trolley in any manner, what is the speed of the CM of the (trolley + child) system ?

The cylindrical tube of a spray pump has a cross-section of 8.0 cm^2 one end of which has 40 fine holes each of diameter 1.0 mm. If the liquid flow inside the tube is 1.5 m min^-1 , what is the speed of ejection of the liquid through the holes ?

A metre-long tube open at one end, with a movable piston at the other end, shows resonance with a fixed frequency source (a tuning fork of frequency 340 Hz) when the tube length is 25.5 cm or 79.3 cm. Estimate the speed of sound in air at the temperature of the experiment. The edge effects may be neglected.