Two 15 N weights A and B are connected by a massless string hanging over a smooth frictionless peg. If a third weight of 15 N is added to A and the system is released, by how much is the force on the peg increased?

When paralleling a generating unit to a power system, if the synchroscope indicates that the incoming machine is running slower than the system:

a.  The field current should be increased

b.  The power input to the prime mover should be increased slightly

c.  The power input to the prime mover should be decreased slightly

d.  The synchronizing switch should be closed just after it indicates zero phase angle difference.

In a power system using both Hydro and thermal generation, the proportion of hydro generation can be increased by.

a.  Increasing the price of water

b.  Reducing the price of water

c.  Increasing the field current of the Hydro generators

d.  Used salt water

. For quick preparation of a cup of hot chocolate in a cafeteria, cocoa powder and sugar

are added in a cup of water and the solution is heated by direct steam injection. If the

initial temperature of all the ingredients is 15 ℃, the final temperature is 95℃, the mass

of the solution is 150g initially, and the heat capacity of the solution is 3.8 kJ/kg ℃,

calculate how much saturated steam at 110 ℃ will be used. State your assumptions.