Answer:
a) Em = 332.8 J
, b) # jump = 13, c)
It is reasonable since there are not too many jumps
, d) lower the calories consumed
Explanation:
a) Let's use energy conservation
Initial. On the floor
Em₀ = K = ½ m v²
Final. The highest point
Emf = U = m g h
Energy is conserved
Em₀ = Emf
½ m v² = m g h
h = ½ v² / g
h = ½ 3.2² /9.8
h = 0.52 m
b) When he was at home he maintained his weight with 2500 cal / day. In his parents' house he consumes 3500 cal / day, the excess of calories is
Q = 3500 -2500 = 1000cal / day
Let's reduce this value to the SI system
Q = 1000 cal (4,184 J / 1 cal) = 4186 J / day
Now the energy in each jump is
Em = K = ½ m v²
Em = ½ 65 3.2²
Em = 332.8 J
They indicate that the body can only use 25% of this energy
Em effec = 0.25 332.8 J
Em effec = 83.2 J
This is the energy that burns the body
Let's use a Proportion Rule (rule of three), if a jump spends 83.2J how much jump it needs to spend 1046 J
# jump = 1046 J (1 jump / 83.2 J)
# jump = 12.6 jumps / day
# jump = 13
c) It is reasonable since there are not too many jumps
d) That some days consume more vegetables to lower the calories consumed
