Answer:
Density of 18.0-karat gold mixture is
.
Explanation:
A mixture of 18 parts gold, 5 parts silver, and 1 part copper.
Let mass of gold be 18x
Let the mass of silver be 5x
Let the mass of copper be 1x
The density of gold = 
The density of silver = 
The density of copper =

Volume of the gold in the mixture = 
Volume of the silver in the mixture = 
Volume of the copper in the mixture = 
Mass of the mixture = M = 18x+5x+1x =24x
Volume of the mixture = 
Density of the mixture:

Answer:
= 2.83
Explanation:
F number (N) is given by the formula;
F- number = f/D
where f = focal length of lens and D = diameter of the aperture
Therefore;
F number = 17 cm/6 cm
<u> = 2.83</u>
Answer:
1) Weight on Mercury

Explanation:
do the same to the rest and use your calculator to find the weight in N.
When potential energy <u>decreases</u>, kinetic energy increases.
Answer:
<u>Mirrors</u>
Explanation:
In Solar thermal power generation system, mirrors are used to collect and focus sunlight onto a fluid pipe to produce high temperature required to generate electricity.
There are two main components: mirrors capture and focus light onto a receiver. The heat transfer fluid is circulated in the receiver. Steam is produced which is converted to mechanical energy in a turbine. It powers a generator and electricity is produced.