A: Buoyant force is equal to the weight
Kinetic Energy = 1/2 * mv²
Kinetic Energy = 14 J, v = 2.3 m/s , m = ?
14 = 1/2 * m* 2.3²
14 = 0.5*m*2.3*2.3
m = 14 / (0.5*2.3*2.3)
m = 5.29 kg.
Mass = 5.29 kg.
If you are pushing the coin across the table at a constant rate, the friction of the table and the horizontal force of your hand pushing are equal, and the coin itself moves at a constant rate. If you push a coin and let it go, there is no horizontal force keeping the coin going. Friction slows the coin to a stop. In both cases, the gravitational downward pull of Earth is equally but oppositely resisted by the upward push of table on the coin.
Answer:
a

b

Explanation:
From the question we are told that
Their distance apart is 
The wavelength of each source wave 
Let the distance from source A where the construct interference occurred be z
Generally the path difference for constructive interference is

Now given that we are considering just the straight line (i.e points along the line connecting the two sources ) then the order of the maxima m = 0
so

=> 
=> 
Generally the path difference for destructive interference is

=> 
=> 
substituting values

=> 
So


and

=> 
=> 