energy never disappears, for example, if you give some kinetic energy to a ball and it stops few seconds later, friction steals this energy to ground which ball was going on. "Law of Conservation of Energy" tell us that energy can't disappear
F=-ks
F=-(390)(.45)
F=-175.5 N
Work=force x displacement
Work= 175.5(0.45)
Work= 78.98 J
Work = ∆E =78.98 J
Answer=79J (first option)
Answer:
0.0268 m
Explanation:
Draw a free body diagram of the block. There are three forces: weight force mg pulling down, buoyancy of the oil B₁ pushing up, and buoyancy of the water B₂ pushing up.
Sum of forces in the y direction:
∑F = ma
B₁ + B₂ − mg = 0
ρ₁V₁g + ρ₂V₂g − mg = 0
ρ₁V₁ + ρ₂V₂ = m
ρ₁V₁ + ρ₂V₂ = ρV
ρ₁Ah₁ + ρ₂Ah₂ = ρAh
ρ₁h₁ + ρ₂h₂ = ρh
(930 kg/m³)h₁ + (1000 kg/m³)h₂ = (968 kg/m³) (4.93 cm)
Since the block is fully submerged, h₁ + h₂ = 4.93 cm.
(930 kg/m³) (4.93 cm − h₂) + (1000 kg/m³)h₂ = (968 kg/m³) (4.93 cm)
h₂ = 2.68 cm
h₂ = 0.0268 m
Access to Alternative Source of Fuel.
Reduce Surface Toxicity.
Lower Energy Cost.
More Jobs.
Buys More Time.
Requires Huge Amounts of Water.
Possible Water Contamination.
May Trigger Earthquakes.
