Explanation:
Electromagnetic waves are different from sound or water waves in such a way that water and sound waves are called mechanical waves that requires a material medium for their propagation.
Electromagnetic waves do no require a material medium for propagation.
- Electromagnetic waves are carried or transported by radiation and this can be passed through vacuums and different other materials.
- But mechanical waves such as water and sound waves requires a material medium for their propagation.
- They cannot pass through a vacuum.
Question 4 is true, question 5 is B.
Answer:
When the metal wire in an incandescent lightbulb glows when the light is switched on and stops glowing when it is switched off, this is an example of resistance, which provides light and heat.
Explanation:
Answer:
The length of chain she is allowed is 1.169 ft
Explanation:
The given parameters are;
The linear density of the chain = 0.83 lb/ft
The weight limit of the chain she wants = 1.4 lb
The formula for linear density = Weight/length
Therefore, in order to keep the chain below 1.4 lb, we have;
Linear density = Weight/length
Therefore;
The maximum length she wants = Weight/(Linear density)
Which gives;
The maximum length she wants = 1.4 lb/(0.83 lb/ft) =1.169 ft
Therefore;
The length of chain she is allowed = 1.169 ft.