Explanation:
The velocity of sound depends on the density of the medium. So we need to find the density of air at each set of conditions. The density of air is:
ρ = (Pd / (Rd T)) + (Pv / (Rv T))
where Pd and Pv are the partial pressures of dry air and water vapor,
Rd and Rv are the specific gas constants of dry air and water vapor,
and T is the absolute temperature.
At the first condition:
Pv = 31.7 mmHg = 4226.3 Pa
Pd = 650 mmHg - 31.7 mmHg = 618.3 mmHg = 82433 Pa
Rv = 461.52 J/kg/K
Rd = 287.00 J/kg/K
T = 30°C = 303.15°C
ρ = (82433 / 287.00 / 303.15) + (4226.3 / 461.52 / 303.15)
ρ = 0.94746 + 0.03021
ρ = 0.97767 kg/m³
At the second condition:
Pv = 0 Pa
Pd = 650 mmHg = 86660 Pa
Rv = 461.52 J/kg/K
Rd = 287.00 J/kg/K
T = 0°C = 273.15°C
ρ = (86660 / 287.00 / 273.15) + (0 / 461.52 / 273.15)
ρ = 1.1054 + 0
ρ = 1.1054 kg/m³
The square of the velocity of sound is proportional to the ratio between pressure and density:
v² = k P / ρ
Since the atmospheric pressure is constant, we can say it's proportional to just the density:
v² = k / ρ
Using the first condition to find the coefficient:
(340)² = k / 0.97767
k = 113018.652
Now finding the velocity of sound at the second condition:
v² = 113018.652 / 1.1054
v = 319.75
<span>Lab Safety Rules:
Report all accidents, injuries, and breakage of glass or equipment to instructor immediately. Keep
pathways clear by placing extra items (books, bags, etc.) on the
shelves or under the work tables. If under the tables, make sure that
these items can not be stepped on. Long hair (chin-length or longer) must be tied back to avoid catching fire. Wear sensible clothing including footwear. Loose clothing should be secured so they do not get caught in a flame or chemicals.<span>Work quietly — know what you are doing by reading the assigned experiment before you start to work. Pay close attention to any cautions described in the laboratory exercises</span> Do not taste or smell chemicals.<span> Wear safety goggles to protect your eyes when heating substances, dissecting, etc.</span> Do not attempt to change the position of glass tubing in a stopper.<span> Never point a test tube being heated at another student or yourself. Never look into a test tube while you are heating it.</span><span>Unauthorized experiments or procedures must not be attempted.</span>Keep solids out of the sink. Leave your work station clean and in good order before leaving the laboratory. Do not lean, hang over or sit on the laboratory tables. Do not leave your assigned laboratory station without permission of the teacher. Learn the location of the fire extinguisher, eye wash station, first aid kit and safety shower. Fooling
around or "horse play" in the laboratory is absolutely forbidden.
Students found in violation of this safety rule will be barred from participating in future labs and could result in suspension. Anyone wearing acrylic nails will not be allowed to work with matches, lighted splints, Bunsen burners, etc. Do not lift any solutions, glassware or other types of apparatus above eye level. Follow all instructions given by your teacher.Learn how to transport all materials and equipment safely. No eating or drinking in the lab at any time! </span>
Answer:
L = 130 decibels
Explanation:
The computation of the sound intensity level in decibels is shown below:
According to the question, data provided is as follows
I = sound intensity = 10 W/m^2
I0 = reference level = 
Now
Intensity level ( or Loudness)is




Therefore
L = 13 bel
And as we know that
1 bel = 10 decibels
So,
The Sound intensity level is
L = 130 decibels
Answer:
the answer is C
Explanation:
gravity forces down not up or sideways.
Answer:
- solution,
- Given
- load =400N
- ld=0.2m
- ed=0.6m
- effort =150N
Explanation:
efficiency =output work/input work ×100%
l×ld/e×ed×100%
400×0.2/150×0.6×100%
80/90×100%
88.89%ans