The mechanical energy at top =Mechanical energy at bottom
- Mass=m=54kg
- Height=h=51m
- Acceleration due to gravity=g=10m/s^2
- Velocity=v=2.6m/s

- Final energy at bottom=The kinetic energy










Answer:
34.6 m/s
Explanation:
From conservation of momentum, the sum of initial and final momentum are equal. Momentum is a product of mass and velocity. Initial mass will be 42.8+31.5+25.9=100.2 kg
Final mass will be 31.5+25.9=57.4 kg
From formula of momentum
M1v1=m2v2
Making v2 the subject of the formula then

Substitute 100.2 kg for M1, 19.8 m/s fkr v1 and 57.4 kg for m2 then

Answer:
The ball will have a kinetic energy of 0.615 Joules.
Explanation:
Use the kinetic energy formula

The kinetic energy at the moment of leaving the hand will be 0.615 Joules. (From there on, as it ball is traveling upwards, this energy will be gradually traded off with potential energy until the ball's velocity becomes zero at the apex of the flight)
Answer:
32 bottles
Explanation:
If we create a free body diagram on the child we have his weight and the bouyant force
W-B=0
They must be equal to mantain equilibrium on the body and he can stay floating, this force is equivalent to the weight of water displaced
W=B=Ww
Mg=mg
32 kg=mass of water displaced
1 kilogram per liter (kg/L) is the density of water, this means that 32 Liters of water are displaced and since the bottles can retain 1 liter, the child needs 32 bottles
Answer:
energy which a body possesses by virtue of being in motion.
Explanation: