Objects should be cooled before their mass is determined on a sensitive balance because it could damage the balance. Also, because it would give you wrong reading of the mass. Hot objects would warm the air around it. A warm air would expand and would produce convection as it rises causing to give the object a mass that is less than the actual. Another reason would be it would cause instability in the readings, the mass would fluctuate every now and then due to the convection currents around the object. It is always recommended to weigh the masses of objects that are in room temperature.
If a man pushes on a wall with some force then according to Newton's third law, wall will also apply force on man with same magnitude but opposite in direction.
Answer:


Explanation:
G = Gravitational constant = 6.67 × 10⁻¹¹ m³/kgs²
= Mass of sphere = 2000 kg
= Mass of other sphere = 2.1 kg
r = Distance between spheres
Force of gravity is given by

The gravitational force is 

The gravitational force is 
If you'r referring to some objects, it means that the mass of the object is less than the water so it floats. If the mass of an object is greater than the mass of the water, it will sink. Compare it to a balloon, helium makes it rise, while normal air makes it sink.
Answer: 3.08 !! <3
Explanation: im sorry but im not sure y i just got the answer wrong and this is wut it told me was right :)