1. The is the sum of all forces acting on an object. a. When forces act in the same direction, you can the

forces together.

b. If forces act in the direction, add them just as you

add positive and negative numbers.

2. Forces are or unbalanced.

a. If the net force acting on an object is 0 N, the forces acting on it are forces.

b. forces do not affect the motion of an object.

c. forces are the result of a net force that does not equal

zero that acts on an object.

d. The motion of an object changes when forces act on it.

The process in which the nucleus of an atom splits into two lighter atoms, releasing a large amount of energy is nuclear

Na food processing facility, a spherical container of inner radius r1 5 40 cm, outer radius r2 5 41 cm, and ther- mal conductivity k 5 1.5 w/m · k is used to store hot water and to keep it at 100°c at all times. to accomplish this, the outer surface of the container is wrapped with a 800-w electric strip heater and then insulated. the temperature of the inner surface of the container is observed to be nearly 120°c at all times. as- suming 10 percent of the heat generated in the heater is lost through the insulation, (a) express the differential equation and the boundary conditions for steady one-dimensional heat conduction through the container, (b) obtain a relation for the variation of temperature in the container material by solving the differential equation, and (c) evaluate the outer surface tempera- ture of the container. also determine how much water at 100°c this tank can supply steadily if the cold water enters at 20°c.

In a heat engine if 1000 j of heat enters the system the piston does 500 j of work, what is the final internal energy of the system if the initial energy was 2000 j? 1. write the equation 2.list out your known variables 3.plug the numbers into the equations 4.solve 5.write your solution statement that includes initial energy and final