Answer:
The heavier piece acquired 2800 J kinetic energy
Explanation:
From the principle of conservation of linear momentum:
0 = M₁v₁ - M₂v₂
M₁v₁ = M₂v₂
let the second piece be the heavier mass, then
M₁v₁ = (2M₁)v₂
v₁ = 2v₂ and v₂ = ¹/₂ v₁
From the principle of conservation of kinetic energy:
¹/₂ K.E₁ + ¹/₂ K.E₂ = 8400 J
¹/₂ M₁(v₁)² + ¹/₂ (2M₁)(¹/₂v₁)² = 8400
¹/₂ M₁(v₁)² + ¹/₄M₁(v₁)² = 8400
K.E₁ + ¹/₂K.E₁ = 8400
Now, we determine K.E₁ and note that K.E₂ = ¹/₂K.E₁
1.5 K.E₁ = 8400
K.E₁ = 8400/1.5
K.E₁ = 5600 J
K.E₂ = ¹/₂K.E₁ = 0.5*5600 J = 2800 J
Therefore, the heavier piece acquired 2800 J kinetic energy
Power = 1800W (or 1.8KW by dividing by 1000)
Time = 3 hours
Power = energy/ time
1.8KW = energy/ 3
x3
5.4Kw/h= energy
(5.4KJ or 5400J used)
$0.15 Kw/h
$0.15 X 5.4 = 0.81
Thus, cost $0.81
Hope this helps!
Motorcycle helmets are padded to give the rider the protection they require in case of accidents. Any hit to the head is absorbed by the padding and the rider is saved from any kind of fatal injury. Whenever a motorcycle rider falls from his motorcycle, there is every possibility that the head will hit the ground first. If the padding was not there, then the rider would get the direct impact of hitting. As most of the pressure of the hit gets absorbed by the inner padding of the helmet, so the rider is saved from the fatal accident. It does not mean that the driver will not have minor injuries but by all chance his life would be saved.
<span>In an internal combustion engine, heat flow into a gas causes it to expand.
The application of direct force to specific parts of the engine will produce </span>expansion of the high-temperature<span> and high-</span>pressure<span> gases. Which will transform the chemical energy from the fuel (such as gasoline or oi) into mechanical energy.</span>
Yes, an object can have both of these at the same time. Potential energy is energy that is stored in an object. Kinetic energy is the energy that is associated with motion. So what you have to have is an object that is in motion but still has more energy that it has yet to convert into kinetic energy.
