Answer:
Objects with mass exert forces on each other via the force of gravity. This force is proportional to the mass of the two interacting objects, and is inversely proportional to the square of the distance between them. The factors G, M, and r are the same for all masses at the surface of the Earth.
A 5kg box rests on a table. a 3 kg box rests on top of the 5 kg box. what is the normal force from the table?
a. 19.6 n
b. 29.4 n
c. 49 n
d. 78.4 n
==> The total mass resting on the table is (5 kg + 3 kg) = 8 kg.
==> The total weight of that mass is (8 kg) x (9.8 m/s) = 78.4 newtons
==> The boxes are stacked. So the table doesn't know if the weight on it is coming from one box, 2 boxes, 3 boxes, or 100 boxes in a stack. The table only knows that there is a downward force of 78.4 newtons on it.
==> The table stands in a Physics classroom, and it soaks up everything it hears there. It knows that every action produces an equal and opposite reaction, and that forces always occur in pairs.
Ever since the day it was only a pile of lumber out behind the hardware store in the rain, the table has known that in order to maintain the good reputation of tables all over the world, it must resist the weight of anything placed upon it with an identical upward force. This is the normal thing for all good tables to do, up to the ultimate structural limit of their materials and construction, and it is known as the "normal force".
So the table in your question provides a normal force of 78.4 newtons. (d)
When two things are the same temperature:
А
Heat transfer between the two things stops
B
Their molecules stop moving
They have the same number of molecules
D
Their molecules move at the same average speed
Answer:
When two objects are in thermal equilibrium they are said to have the same temperature. During the process of reaching thermal equilibrium, heat, which is a form of energy, is transferred between the objects.