A: The battery is a store of internal energy (shown as chemical energy). The energy is transferred through the wires to the lamp, which then transfers the energy to the surroundings as light. These are the useful energy transfers - we use electric lamps to light up our rooms.
B: In the case of the light bulb the 95J of energy transferred as heat is wasted energy as it is not useful because the purpose of the device is to produce light.
SORRY I ONLY HAVE ANSWERS FOR A AND B
Amount of work done is zero and so power = 0 watts.
<u>Explanation:</u>
Power is the rate at which work is done, or W divided by delta t. Since the barbell is not moving, the weightlifter is not doing work on the barbell.Therefore, if the work done is zero, then the power is also zero.It may seem unusual that the data given in question is versatile i.e. A weightlifter exerts an upward force on a 1000-N barbell and holds it at a height of 1 meter for 2 seconds. But, still the answer is zero watts , this was a tricky question although conceptual basis of question was good! Power is dependent on amount of work done which is further related to displacement and here the net displacement is zero ! Hence, amount of work done is zero and so power = 0 watts.
The weight changes but the mass will stay the same.
Answer: Option B
Explanation : When a negatively charged object A gets in contact with the neutral object B, the negative charge of object will induce the opposite charges on object B. Hence, there will be a positive charge on object B