I would say that there shouldn't be any calls on a plane while in-flight because you never know what someone is calling for. It can lead to a bad situation like 9/11 or any form of terrorism.
I had to look for the options and here is my answer:
Given that a guitar string has a basic frequency of 500hz, the frequency that can be set for this into resonant vibration would be 1500 Hz. The resonant vibration here is necessary in musical instruments because it delivers a vibrating system which leads to a higher amplitude at a particular frequency.
Answer:
The magnitude of the force exerted by the ball on the catcher is 1.9 × 10² N
Explanation:
Hi there!
Let´s find the acceleration of the ball that makes it stop when caught by the catcher. The acceleration can be calculated from the equation of velocity considering that it is constant:
v = v0 + a · t
We know that initially the ball was traveling at 25 m/s, so, if we consider the position of the catcher as the origin of the frame of reference, then, v0 = -25 m/s. We also know that it takes the ball 20 ms (0.02 s) to stop (i.e. to reach a velocity of 0). Then using the equation of velocity:
v = v0 + a · t
0 m/s = -25 m/s + a · 0.020 s
25 m/s/ 0.020 s = a
Now, using the second law of Newton, we can calculate the force exerted by the catcher on the ball:
F = m · a
Where:
F = force.
m = mass of the ball.
a = acceleration.
F = 0.150 kg · (25 m/s/ 0.020 s) = 1.9 × 10² N
According to Newton´s third law, the force exerted by the ball on the catcher will be of equal magnitude but opposite direction. Then, the force exerted by the ball on the catcher will have a magnitude of 1.9 × 10² N.
Answer:
D. Hydrogen combines with oxygen to form water.
Explanation:
Hydrogen combining with oxygen to form water is a typical example of chemical reaction.
During a chemical reaction, atoms of elements are rearranged. Most chemical reactions obey the law of conservation of mass which states that "matter is neither created nor destroyed in a chemical reaction but atoms are simply rearranged".
The other choices given are nuclear reactions. In such reactions, atoms are not rearranged but are simply destroyed and made in the process.
Answer:
The person's ear canal length is 2.91 cm.
Explanation:
Given that,
Frequency = 3000 Hz
Temperature = 30°C
We need to calculate the speed
Using equation of sound wave with temperature
[texs]v(t)=331+0.6\times T[/tex]
Put the value of T
We need to calculate the length
Using formula of closed organ pipe
Where, L = length
v = velocity
f = frequency
Put the value into the formula
Hence, The person's ear canal length is 2.91 cm.
