Answer:
Part a)

Part b)
t = 12 s
Explanation:
Part a)
Tension in the rope at a distance x from the lower end is given as

so the speed of the wave at that position is given as

here we know that

now we have


Part b)
time taken by the wave to reach the top is given as




Answer:

Explanation:
For this problem, we can use Boyle's law, which states that for a gas at constant temperature, the product between pressure and volume remains constant:

which can also be rewritten as

In our case, we have:
is the initial pressure
is the initial volume
is the final pressure
Solving for V2, we find the final volume:

Answer: Energy consumption and sustainability is important so that it remain available for future generation.
Explanation:
1. The home furnaces are likely to require fuel like coal, which will directly emit carbon dioxide and carbon monoxide gases. These should be replaced with the electrical furnaces. The old or more power consuming air conditioners should be replaced with new ones.
2. The water heaters should be tankless so their capacity to heat more water could be possible. The water heaters should be electricity saving.
3. Washer and dryers should be water savy and electricity savy. A front-loading washing machine is useful energy saver.
4. The LED lights are more electricity saving than conventional bulbs. Halogen lights are also electricity saving.
Answer:
h = 3.1 cm
Explanation:
Given that,
The volume of a oil drop, V = 10 m
Radius, r = 10 m
We need to find the thickness of the film. The film is in the form of a cylinder whose volume is as follows :

So, the thickness of the film is equal to 3.1 cm.