There are two types of equilibrium in mechanics.One is called static equilibrium and the other one is called dynamic equilibrium. In both the cases of mechanical equilibrium,the net force acting on the particle is zero.
A body is said to be in dynamic equilibrium if the net force acting on a moving body is zero.There will be no acceleration of the body.The body will continue its uniform motion without change in its direction and speed.
The body is said to be in static equilibrium if the net force acting on a body at rest is zero.As the net force is zero,the body will not undergo motion. It is due to the inertia of the body.
The two equilibrium are the direct consequences of Newton's first law which tells that a body will continue to be at state of rest or uniform motion along a straight line unless and until it is compelled by some external unbalanced force.Hence as long as net force on the body is zero,the body at rest will satisfy static equilibrium.
Out of the four options given in the question only third option is right which tells that a book that has no net force acting on it and sitting on a table is under static equilibrium. If the net force is not zero,the body can not be under static equilibrium.The book resting on a table imparts a force equal to its weight on the table and table in turn gives the normal reaction in vertically upward direction.The gravity pulls the book in vertically downward direction with a force equal to its weigh.Hence the net force is zero.So the table will be at rest.
If the net force is not zero,the body can not be under static equilibrium.
Hence option 3 is right.
Answer:
saddle weighs 250 newtons. The mass of the saddle is ____250/9.8 kg______ kilograms. Use g = 9.8 N/kg for gravity.
Nonmetals often share or gain
electrons. The nonmetals in the periodic table increases as you move to the
right and decreases as you go down. This is because, the smaller the atom, the
reactive it gets due to less electron attached to the orbits of the atom. The
reactivity of nonmetals is arranged in decreasing order.
<span>
Carbon
</span>
Nitrogen
Oxygen
Fluorine
Phosphorus
<span>
Sulfur</span>
Chlorine
<span>
Selenium</span>
<span>
Bromine</span>
<span>
Iodine</span>
The phenomenon of "weightlessness" occurs when there is no force of support on your body. When your body is effectively in "free fall", accelerating downward at the acceleration of gravity, then you are not being supported.
Kinetic and potential energies are found in all objects. If an object is moving, it is said to have kinetic energy (KE). Potential energy (PE) is energy that is "stored" because of the position and/or arrangement of the object.
