Answer:
F = 263.51 N
Explanation:
given,
diameter of wheel = 78 cm
diameter of axle = 14.8 cm
Force exerted on the rim of wheel = 150 N
Force applied outside the axle = ?
To prevent rotation wheel from rotating the Force 'F' should be applied outside of the axle.
Net momentum about the center of mass should be zero
now,
Moment of about center due to 150 N = moment about center due to F on axle
7.4 F = 1950
F = 263.51 N
Hence, Force exerted outside of the axle in order to prevent the wheel from rotating is equal to 263.51 N.
Internal energy.
Explanation:
In any substance/object, the particles inside it (atoms/molecules) constantly move in random directions and with random speeds (this motion is called Brownian motion). As a result, the particles have some kinetic energy (which is proportional to the temperature of the substance). Moreover, the particles interact with each other due to the presence of electrostatic intermolecular forces, and as a result, the particles also have some potential energy.
The sum of the kinetic energies and potential energies of the particles in a substance is called internal energy.
Words less true are seldom if ever spoken.
You might see the word alloy described as a "mixture of metals", but that's a little bit misleading because some alloys contain only one metal and it's mixed in with other substances that are nonmetals (cast iron, for example, is an alloy made of just one metal, iron, mixed with one nonmetal, carbon). The best way to think of an alloy is as a material that's made up of at least two different chemical elements, one of which is a metal. The most important metallic component of an alloy (often representing 90 percent or more of the material) is called the main metal, the parent metal, or the base metal. The other components of an alloy (which are called alloying agents) can be either metals or nonmetals and they're present in much smaller quantities (sometimes less than 1 percent of the total). Although an alloy can sometimes be a compound (the elements it's made from are chemically bonded together), it's usually a solid solution (atoms of the elements are simply intermixed, like salt mixed with water).
