equal and opposite reaction.
Answer:
420J
Explanation:
Power is the time rate of change in energy. Power is the ratio of energy to time. The S.I unit of power is in watts.
Given that the flash lasts for 1/675 s, power output is 2.7 * 10⁵ W. Hence:
Power = Energy / time
Substituting:
2.7 * 10⁵ W = Energy / (1/675)
Energy = 2.7 * 10⁵ W * 1/675 = 400J
Therefore the energy emitted as light is 400J.
Since the conversion of electric energy to light is 95% efficient, hence the energy stored as electrical energy is:
Energy(capacitor) = 5% of 400J + 400J = 0.05*400 + 400
Energy(capacitor) = 420J
Answer:
500J
Explanation:
The arrow will have an energy of 500J after it has been released from its state of rest.
This is compliance with the law of conservation of energy which states that "in every system, energy is neither created nor destroyed but transformed from one form to another".
- The energy at rest which is the potential energy is 500J
- This energy will be converted to kinetic energy in total after the arrow has been released.
- This way, no energy is lost and we can account for the energy transformations occurring.
The correct answer is
<span>A. decreasing the current
In fact, the magnetic field produced by a current carrying wire is given by
</span>

<span>where
</span>

is the vacuum permeability
<span>I is the current in the wire
r is the distance from the wire at which the field is calculated
We see from the formula that the intensity of the field, B, is directly proportional to the current I, so if the current decreases, the magnetic field strength B decreases as well.</span>