Mechanical energy E = mgh + 1/2mv²
When he starts, let h = 0 ⇒ E₁ = 1/2mv₁²
When he reaches height h ⇒ E₂ = mgh + 1/2mv₂²
Without friction, energy is conserved at all times.
E₁ = E₂
↓
1/2mv₁² = mgh + 1/2mv₂²
↓
1/2v₁² = gh + 1/2v₂²
↓
gh = 1/2(v₁² - v₂²)
↓
h = (v₁² - v₂²) / (2g)
Answer:
the ball will go up 3s and down 3s
v=gt
where t=3s and g=9.8m/s^2
distance=v0(t)+(1/2)gt^2
where initial velocity (v0)=0
Explanation:
The total energy produced by the generator is 3.45 kJ. Of this energy, 2.23 kJ are lost because friction and electrical resistance, so this amount of energy is converted into thermal energy. This means that the rest of the energy is available as electric energy, and it is equal to: