Potential energy behind dams
Answer:
Current is in phase with voltage in a resistive circuit. Note that the wave form for power is always positive, never negative for this resistive circuit. This means that power is always being dissipated by the resistive load, and never returned to the source as it is with reactive loads.Explanation:
Answer:
90°
Explanation:
The angle will be 90° when momentum for a system can be conserved in one direction while not being conserved in another.
The example can be
If we apply force on an object horizontally in west direction, then as in other direction south or north we cannot apply the principal of momentum conservation.
Answer:
b) 2ft/s
Explanation:
A scalar has only magintude, not direction
6.2m, 3kg, and -100 o C are all scalars because they only have magnitude.
2ft/s is not a scalar because it has a direction.
The situation given above can be answered through the concept of the First Law of thermodynamics which states that the change in internal energy is equal to the difference between the work done and the heat added to the system. The work done by the object is negative and the heat added is positive.
change in internal energy = -500J + 1400 J = 900 J
