Answer:
average for silk =141"
average for cotton =96"
average for nylon = 70"
if you desire a slower falling parachute to protect the body from damage,
silk is the best
if you desire a faster falling parachute to escape enemy bullets,
nylon is the best
Explanation:
Homework 1
Problem Solving
1. Kelvin and Xavier were doing an investigation on parachutes. One of them suggested that the type of material the parachute was made from had an effect on how long it took to reach the ground. Their results are given in
the table below.
(a) Calculate the average time in seconds for each material.
Time taken for parachute to reach the ground (seconds)
MATERIAL
1st TRY
2nd TRY
3rd TRY
AVERAGE
Sik
144
140 average of 3 = 141
139
Cotton
98
96 average of 3 = 96
94
Nylon
72
68 average of 3 = 70
70
Answer:
number of moles of NaCl produce = 12 mol
Explanation:
Firstly, we need to write the chemical equation of the reaction and balance it .
Na(s) + Cl2(g) → NaCl(s)
The balanced equation is as follows:
2Na(s) + Cl2(g) → 2NaCl(s)
1 mole(71 g) of chlorine produces 2 moles(117 g) of sodium chloride
6 mole of chlorine gas will produce ? mole of sodium chloride
cross multiply
number of moles of NaCl produce = 6 × 2
number of moles of NaCl produce = 12 moles
number of moles of NaCl produce = 12 mol
Protein would be the main one.
<u>Answer:</u> The amount of water required to prepare given amount of salt is 398.4 mL
<u>Explanation:</u>
To calculate the volume of solution, we use the equation used to calculate the molarity of solution:

We are given:
Molarity of solution = 0.16 M
Given mass of manganese (II) nitrate tetrahydrate = 16 g
Molar mass of manganese (II) nitrate tetrahydrate = 251 g/mol
Putting values in above equation, we get:

Volume of water = Volume of solution = 398.4 mL
Hence, the amount of water required to prepare given amount of salt is 398.4 mL
Answer: There are five significant figures in 865,010.
Explanation:
When a degree of accuracy is stated by each digit present in a mathematical figure then it is called a significant figure.
Rules for counting significant figures is as follows.
- Any non-zero digits and zeros present between a non-zero figure are counted. For example, 3580009 has seven significant figures.
- Trailing zeros are counted in a non-zero figure. For example, 0.00250 has three significant figures.
- Leading zeros are not counted. For example, 0.0025 has two significant figures.
So, in the given figure 865010 has five significant figures and the trailing zero will not be counted.
Thus, we can conclude that there are five significant figures in 865,010.