The distance an object falls from rest through gravity is 
                        D  =  (1/2) (g) (t²) 
           Distance  =  (1/2 acceleration of gravity) x (square of the falling time)
We want to see how the time will be affected 
if  ' D ' doesn't change but ' g ' does. 
So I'm going to start by rearranging the equation
to solve for ' t '.                                                      D  =  (1/2) (g) (t²)
Multiply each side by  2 :         2 D  =            g    t²  
Divide each side by ' g ' :      2 D/g =                  t² 
Square root each side:        t = √ (2D/g)
Looking at the equation now, we can see what happens to ' t ' when only ' g ' changes:
  -- ' g ' is in the denominator; so bigger 'g' ==> shorter 't'
                                             and smaller 'g' ==> longer 't' .-- 
They don't change by the same factor, because  1/g  is inside the square root.  So 't' changes the same amount as  √1/g  does.
Gravity on the surface of the moon is roughly  1/6  the value of gravity on the surface of the Earth.
So we expect ' t ' to increase by  √6  =  2.45 times.
It would take the same bottle  (2.45 x 4.95) = 12.12 seconds to roll off the same window sill and fall 120 meters down to the surface of the Moon.
        
             
        
        
        
Answer:
Usually the coefficient of friction remains unchanged
Explanation:
The coefficient of friction should in the majority of cases, remain constant no matter what your normal force is. When you apply a greater normal force, the frictional force increases, and your coefficient of friction stays the same. Here's another way to think about it: because the force of friction is equal to the normal force times the coefficient of friction, friction is increased when normal force is increased.
Plus, the coefficient of friction is a property of the materials being "rubbed", and this property usually does not depend on the normal force.
 
        
                    
             
        
        
        
Answer:
least distance= 13mm
ratio of the lattice = 1 : 0.71 : 0.58
Explanation:
given λ₁ = 650nm = 650×10⁻⁹m,  λ₂ = 500nm = 500×10⁻⁹m
 
        
             
        
        
        
Answer:
A: Sound waves produce an echo
Explanation:
because the cup is a hard smooth surface you can hear the voice