Answer:
ΔU = 25.8 J
Explanation:
The gas absorbs 33.3 J of heat, that is, Q = 33.3 J.
The work (W) of expansion can be calculated using the following expression:
W = -P. ΔV
where,
P is the external pressure
ΔV is the change in volume
W = -1.45 × 10⁴ N . m⁻² × (8.40 × 10⁻⁴ m³ - 3.24 × 10⁻⁴ m³) = -7.48 J
The change in the internal energy (ΔU) is:
ΔU = Q + W
ΔU = 33.3 J + (-7.48 J) = 25.8 J
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:
1.88 × 10²² Molecules of CO
Explanation:
At STP for an ideal gas,
Volume = Mole × 22.4 L/mol
Or,
Mole = Volume / 22.4 L/mol
Mole = 0.7 L / 22.4 L/mol
Mole = 0.03125 moles
Now,
No. of Molecules = Moles × 6.022 × 10²³ Molecules/mol
No. of Molecules = 0.03125 × 6.022 × 10²³ Molecules/mol
No. of Molecules = 1.88 × 10²² Molecules of CO
Chemical change or process
