EXAMPLE 4
• A 4200 N piano is pushed up a 3.5 m frictionless
plank that makes an angle of 30 degrees with the
horizontal.
• Calculate the work done by the pushing force in
sliding the piano up the plank at a slow constant
rate.

Oxygen undergoes an isentropic expansion from 120 degree c and 280 kpa absolute to 140 kpa absolute. determine the final temperature of the oxygen and the amount of work per kg of o_2 produced in the process if it is adiabatic.

In what direction does an applied force move an object

Four objects each with charge +2.0×10−7c are located at the corners of a square whose sides are 2.0 m long. part a what quantities can be determined using this information? check all that apply. the electric force on a charged object placed at the center of the square. the mass of each object. the total electric potential energy of the system consisting of the four charged objects. part b find the electric force on a charged object placed at the center of the square.