Point object is an expression that is used in Kinematics. It refers the object whose dimensions are ignored or neglected and is treated as a dot object to simplify the calculations. When the object is treated as a point object it means the whole mass is summed in one point, you can imagine it as a sphere which has the mass and the radius is 0...
Answer:

Explanation:
Orbital velocity is the speed that a body that orbits around another body must have, for its orbit to be stable. For orbits with small eccentricity and when one of the masses is almost negligible compared to the other mass, like in this case, the orbital speed is given by:

Where M is the greater mass around which this negligible body is orbiting, r is the radius of the greater mass and G is the universal gravitational constant. So:

Pour the entire components into water.
First the iron filings can be separated using a magnet as iron is a magnetic element.
By pouring the mixture into water, it allows the salt to dissolve in the water, while the sand will not.
Next we can run this solution through a filtration device to separate the sand from the water.
Now all that's left is to let the water evaporate so that the salt will be exposed that dissolved into the water.
Answer:
(c) position
Explanation:
From the work-energy theorem, the workdone by a force on a body causes a change in kinetic energy of the body.
But, remember that the work done (W) by a force (F) on a body is the product of the force and the distance d, moved by the body caused by the force. i.e
W = F x d
This distance is a measure of the position of the body at a given instance.
Therefore, the work done is given by the force as a function of distance (or position).
Answer:
a The kinetic energy is 
b The height of the center of mass above that position is
Explanation:
From the question we are told that
The length of the rod is 
The mass of the rod
The angular speed at the lowest point is 
Generally moment of inertia of the rod about an axis that passes through its one end is
Substituting values


Generally the kinetic energy rod is mathematically represented as



From the law of conservation of energy
The kinetic energy of the rod during motion = The potential energy of the rod at the highest point
Therefore


