Answer:
The wave speed is calculated below:
Explanation:
Given,
number of waves passed per minute = 8
time period = 1 minute = 60 s
distance between successive wave crests = 20 m
waves passing interval per second = 
Now,
wave speed = 20 m ×
= 
m/s
= 2.67 m/s
Hence the wave speed is 2.67 m/s.
Answer:
1.01 × 10⁵ Pa
Explanation:
At the surface, atmospheric pressure is 1.013 × 10⁵ Pa.
We need to find the total pressure on the air in the lungs of a person to a depth of 1 meter.
Pressure at a depth is given by :
Where
is the density of air, 
So,
Total pressure, P = Atmospheric pressure + 12 Pa
= 1.013 × 10⁵ Pa + 12 Pa
= 1.01 × 10⁵ Pa
Hence, the total pressure is 1.01 × 10⁵ Pa.
The 'formulas' to use are just the definitions of 'power' and 'work':
Power = (work done) / (time to do the work)
and
Work = (force) x (distance) .
Combine these into one. Take the definition of 'Work', and write it in place of 'work' in the definition of power.
Power = (force x distance) / (time)
From the sheet, we know the power, the distance, and the time. So we can use this one formula to find the force.
Power = (force x distance) / (time)
Multiply each side by (time): (Power) x (time) = (force) x (distance)
Divide each side by (distance): Force = (power x time) / (distance).
Look how neat, clean, and simple that is !
Force = (13.3 watts) x (3 seconds) / (4 meters)
Force = (13.3 x 3 / 4) (watt-seconds / meter)
Force = 39.9/4 (joules/meter)
<em>Force = 9.975 Newtons</em>
Is that awesome or what !
The half life is 30 minutes.
30 mins- 1/2 left
60 mins- 1/4 left
90 mins- 1/8 left
120 mins- 1/16 left
120 mins= 2 hours
The medium is the component of communication through which information is transferred. The correct option in the given question is option "c". Medium is actually the means through which communication is done. It can be a an oral message or written message or it can be nonverbal or symbolic. Any kind of message transmission requires a medium and without an medium no message can be transmitted. Whenever people talk on the telephone or write a letter, there has to be a medium for transmitting the message to the person on the other side.
