Nope. It's called 'centripetal' acceleration. The force that created it MAY be gravitational, but it doesn't have to be. For things on the surface of the Earth moving in circles, it's never gravity.
        
             
        
        
        
Water filters and internet to get more knowledge
        
             
        
        
        
Water is more dense then air so it sorta holds the rock as it sinks
        
             
        
        
        
Answer:
Explanation:
For calculating resistance of a conductor , the formula is 
R = ρ l / A , ρ is specific resistance , l is length and A is cross sectional area of wire. 
For first wire length is l₁ , area is A₁ resistance is R₁, for second resistance is R₂ , length is l₂ and area is A₂
Given , l₁ = 2l₂ , A₁ = 4A₂ , area is proportional to square of thickness. 
R₁ / R₂ = I₁A₂ / I₂A₁
= 2l₂ x A₁ / 4 I₂A₁
= 1 / 2 
2R₁ = R₂
Power = V² / R
Ratio of power = (V² / R₁) x (R₂ / V²)
= R₂ / R₁
= 2 .