New evidence may support the theory -> then nothing
New evidence conflicts with the theory => rework theory / create a new one
Answer:
The principle of conservation of energy states that in a closed system, the energy can neither be created nor destroyed between interacting particles and remains constant or transformed from one form to another
In the jet engine, the release of jet changes the number of interacting particles in the engine, and given that energy cannot be created in the instantaneously closed system of the engine, energy is carried away and therefore lost by particles in the jet exhaust
The conservation of energy principle is therefore obeyed in the condition in which the jet engine losses energy by the release of jet
Explanation:
Answer:
AFter 3.5 s, the wagon is moving at: 
Explanation:
Let's start by finding first the net force on the wagon, and from there the wagon's acceleration (using Newton's 2nd Law):
Net force = 250 N + 178 N = 428 N
Therefore, the acceleration from Newton's 2nd Law is:

So now we apply this acceleration to the kinematic expression for velocity in an object moving under constant acceleration:

Answer:
To=20.44 °C
Explanation:
Given that
Velocity , v= 30 m/s
Temperature , T= 20°C
We know that specific heat capacity for air ,Cp=1.005 kJ/kg.K
By using energy conservation ,the stagnation temperature is given as

Now by putting the values in the above equation we get

To= 293.44 K
To= 293.44 - 273 °C
To=20.44 °C
Therefore the stagnation temperature will be 20.44 °C.
D. The number of wave that pass a point in a given amount of time