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:
c
Explanation:
b and d are out, the variables are changed. a would be a repetition, not a replication. c uses the same method and variables with a different control group
Answer: 4Kcal
Explanation:
H= mcø
M=200g
C= 1 cal/g/°c
Ø= 40-20=20°c
H= 200*1*20= 4000calories= 4Kcal
Answer:
The process of dissolving is exothermic when more energy is released when water molecules “bond” to the solute than is used to pull the solute apart. Because more energy is released than is used, the molecules of the solution move faster, making the temperature increase.
Project the image Endothermic Dissolving.
The process of dissolving is endothermic when less energy is released when water molecules “bond” to the solute than is used to pull the solute apart. Because less energy is released than is used, the molecules of the solution move more slowly, making the temperature decrease.
The Henderson-Hasselbalch approximation is for conjugate acid-base pairs in a buffered solution. We're going to call HA a weak acid, and A- its conjugate base. The equation is as follows:
pH = pKa + log([base]/[acid]), where the brackets imply concentrations
Plugging in our symbols and the pKa value, the equation becomes:
pH = 4.874 + log([A-]/[HA])
