The mechanical energy of the girl will be conserved because the system is isolated and the initial potential energy will be equal to final kinetic energy.
<h3>
What is the law of conservation of energy?</h3>
The law of conservation of energy states that energy can neither be created nor destroyed but can be transformed from one form to another.
The change in the potential energy of the launched from a height into the pool without friction from the given height h is calculated by applying the following kinematic equation.
ΔP.E = ΔK.E
where;
- ΔP.E is change in potential energy of the child
- ΔK.E is change in the kinetic energy of the child
mghf - mghi = ¹/₂mv² - ¹/₂mu²
where;
- m is the mass of the girl
- g is acceleration due to gravity
- hi is the initial height of the girl
- hf is the final height when she is launched into the pool
- u is the initial velocity
- v is the final velocity of the girl
Thus, for every closed or isolated system such as this case, mechanical energy is always conserved because the initial potential energy of the girl will be converted into her final kinetic energy.
Learn more about conservation of mechanical energy here: brainly.com/question/332163
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Answer:
0.2932 rad/s
Explanation:
r = Radius = 2 m
= Initial angular momentum = 
= Initial angular velocity = 14 rev/min
= Final angular momentum
= Final angular velocity
Here the angular momentum of the system is conserved
The final angular velocity is 0.2932 rad/s
Answer:
reflection
Explanation:
an example would be looking in the mirror
Answer:
F = 8.6 10⁻¹² N
Explanation:
For this exercise we use the law of conservation of energy
Initial. Field energy with the electron at rest
Em₀ = U = q ΔV
Final. Electron with velocity, just out of the electric field
Emf = K = ½ m v²
Em₀ = Emf
e ΔV = ½ m v²
v =√ 2 e ΔV / m
v = √(2 1.6 10⁻¹⁹ 51400 / 9.1 10⁻³¹)
v = √(1.8075 10¹⁶)
v = 1,344 10⁸ m / s
Now we can use the equation of the magnetic force
F = q v x B
Since the speed and the magnetic field are perpendicular the force that
F = e v B
F = 1.6 10⁻¹⁹ 1.344 10⁸ 0.4
For this exercise we use the law of conservation of energy
Initial. Field energy with the electron at rest
Emo = U = q DV
Final. Electron with velocity, just out of the electric field
Emf = K = ½ m v2
Emo = Emf
.e DV = ½ m v2
.v = RA 2 e DV / m
.v = RA (2 1.6 10-19 51400 / 9.1 10-31)
.v = RA (1.8075 10 16)
.v = 1,344 108 m / s
Now we can use the equation of the magnetic force
F = q v x B
Since the speed and the magnetic field are perpendicular the force that
F = e v B
F = 1.6 10-19 1,344 108 0.4
F = 8.6 10-12 N
