Answer:
A) and B) are correct.
Explanation:
If the object is at rest, it means that no net force is exerted on it.
As the object experiences a downward gravitational force from Earth, in order to be at rest, it must experience an upward force with the same magnitude as the gravitational force on the object.
This force is supplied by the normal force, which can adopt any value in order to meet the condition imposed by Newton´s 2nd Law, and is always perpendicular to the surface on which the object is placed (in this case, the ground).
At a molecular level, this normal force is supplied by the bonded molecules of the ground that behave like small springs being compressed by the molecules of the object, exerting an upward restoring force upward on them.
So, the statements A) and B) are true.
Answer:v=41.23 m/s
Explanation:
Given
mass of heavy object 
distance of 
from the axle 
mass of rock 
Length of rod 
distance of 
from axle 
Net torque acting is
Work done by 
is converted to rock kinetic Energy
thus
Where 
Answer:
i dont understand, can you put it in word form please.
Explanation:
