Answer:
Explanation:
Given
mass of box is m
speed of box is v
coefficient of friction 
Box is moving at a constant speed i.e. Net Force on box is zero
i.e. Frictional Force and Force Applied are Equal
The Rate at which power is generated is
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:
(a) 
(b) 
Solution:
As per the question:
Mass of the object, m = 1.30 kg
Length of the rod, L = 0.780 m
Angular speed, 
Now,
(a) To calculate the rotational inertia of the system about the axis of rotation:
Since, the rod is mass less, the moment of inertia of the rotating system and that of the object about the rotation axis will be equal:
(b) To calculate the applied torque required for the system to rotate at constant speed:
Drag Force, F = 
Answer:
It would be static discharge and conduction
Explanation:
The conduction of static energy is pulled throughout the clothes and left over static electricity is what causes the spark.
