Sis re read it and try it guess it give it your best shot
Answer: a)
Explanation:
The buoyant force, as stated by Archimedes’ principle, is equal to the weight of the liquid that occupies the same volumen as the submerged object, as follows:
Fb = δ.V.g
If this force is larger than the weight of the object (that means that the fluid is denser than the solid), the object floats, which is the case for silver and mercury.
Instead, silver density is larger than water density, which explains why the pure silver ingot sinks.
Finally, as mercury is denser than water, we conclude that for a same object, the buoyant force in mercury is larger than in water (exactly 13.6 times greater).
Answer:
if it is not moving it is zero, like all things that aren't in motion
Explanation:
Answer:
137.2J
Explanation:
Ep= mgh
Given,
and we know, g = 9.81 N/kg
Ep= 2 × 9.81 × 7
Ep= 137.2J
Answer: Rock require larger drag force and to achieve it rock need to move at a very high terminal velocity.
Explanation: Terminal velocity is defined as the final velocity attained by an object falling under the gravity. At this moment weight is balanced by the air resistance or drag force and body falls with zero acceleration i.e. with a constant velocity.
Case 1: Terminal velocity of a piece of tissue paper.
The weight of tissue paper is very less and it experiences an air resistance while falling downward under the effect of gravity.
Downward gravitational force, F = mg
Upward air resistance or friction or drag force will be 
So, paper will attain terminal velocity when mg =
Case 2: Rock is very heavy and require larger air resistance to balance the weight of rock relative to the tissue paper case.
Downward force on rock, F = Mg
Drag force =
Rock will attain terminal velocity when Mg =
Mg > mg
so,
>
And rock require larger drag force and to achieve it rock need to move at a very high terminal velocity.