P. 3984. Estimate how much does the height of the mercury column change in Torricelli's experiment
a) if the device is brought from the room of tempereture to the balcony where the temperature is ;
b) if the device is kept in the room but some drops of water is inserted into the tube.
(In his famous experiment Torricelli created a metre long tube sealed at the top end, filled it with mercury, and set it vertically into a basin of mercury. The column of mercury fell to about 76 cm.)
P. 3985. Two objects of mass m are connected with a rope of length as shown in the figure. The rope can slide in a tube which forms a quarter of a circle, and which is fixed to the edge of the table. Initially of the rope hangs vertically. Friction is negligible.
a) If the system is released, how long does it take for the object on the right handside to descend a distance of , and at that time what are the speeds of the objects?
b) What would be the speeds of the object after covering the same distance if the mass of the rope was m as well?
P. 3988. A small charged bead of mass m and of charge q can move on a frictionless horizontal rod. A pointlike charge Q whose charge is opposite the charge on the bead, is fixed at a point which is at a distance of d from the rod. The bead is a bit displaced from its equilibrium position and then released. Find the period of the resulted oscillatory motion.
Data: Q=10-8 C, q=-10-8 C, m=1 g, d=10 cm.