<text><span class="style10">orces affecting Solids and Fluids (1 of 9)</span><span class="style7">In addition to the fundamental forces, other forces such as frictional, elastic and viscous forces may be encountered. Because of their different natures, solids and fluids appear in some ways to react differently to similar applied forces.When forces are applied to solids they tend to resist. Friction inhibits displacement, but is overcome after a certain limit. Bodies may be deformed by tensions. Fluids, although lacking definite shape, are held together by internal forces. They exert pressure on the walls of the containing vessel. Fluids - by definition - have a tendency to flow; this may be greater in some substances than in others and is governed by the viscosity of the fluid.</span><span class="style10">Statics</span><span class="style7">Newton's first law, stated for a single particle, can also apply to real bodies that have definite sizes and shapes and consist of many particles. Such a body may be in </span><span class="style26">equilibrium</span><span class="style7">, which means it is at rest or moving with constant velocity in a straight line. This means that it is acted on by </span><span class="style26">zero net force</span><span class="style7">, and that it has no tendency to rotate.A body is acted on by zero net force if the total or resultant of all the forces acting on it is zero - i.e. all the forces cancel each other out. If the body is at rest it is in </span><span class="style26">static equilibrium</span><span class="style7">. Studies of such conditions are important in the design of bridges, dams and buildings.</span></text>
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<text><span class="style10">. Equilibrium</span><span class="style7">. The net force on the body is zero. The mass is balanced by the reaction force: R = mg (mg is the gravitational force acting on the mass). The men are pulling with equal force: F = F. The body will not move.</span></text>
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<text>ΓÇó MOTION AND FORCEΓÇó THERMODYNAMICSΓÇó HOW CARS WORK</text>
