a cube just lies inside surface of water when an object of mass 200 kg is placec on it .when 200 kg mass is removed the cube will be exposed by 2 cm . calculate length of cube

can be answered using momentum.

momentum = p

p1= mass1 * velocity1

p1 = p2

therefore

p1 = 6kg * 4m/s

p1 = 24kgm/s

p2=m2 * v2

24 kgm/s = 7kg * v2

v2 = 24 kgm/s / 7kg

v2= 3.42 m/s

it has to be b, about 97 percent.

total distance/total time

(85 + 82)/(5+3)

167/8

20 just over