The time it takes the plane to change its velocity is 9s.
<h3>What is time?</h3>
Time can be defined the measured or measurable period during which an action, process, or condition exists or continues.
To calculate the time it takes the airplane to change its velocity, we use the formula below.
Formula:
- t = (v-u)/a.......... Equation 1
Where:
- a = Acceleration
- v = Final velocity
- u = Initial velocity
- t = time
From the question,
- v = 40 m/s
- u = 22 m/s
- a = 2 m/s²
Substitute these values into equation 1
- t = (40-22)/2
- t = 18/2
- t = 9s
Hence, the time it takes the plane to change its velocity is 9s.
Learn more about time here: brainly.com/question/2854969
Answer:
Explanation:
Given
Volume of fixed chamber 
Initial Temperature 
Final Temperature 
Heat Supplied 
From First law of thermodynamics
Change in internal energy of the system is equal to heat added minus work done by the system

as the volume is fixed therefore work

thus 
for mono-atomic gas is 

and 1 mole contains 
thus No of molecules
No of molecules
Answer:
v = √2G
/ R
Explanation:
For this problem we use energy conservation, the energy initiated is potential and kinetic and the final energy is only potential (infinite r)
Eo = K + U = ½ m1 v² - G m1 m2 / r1
Ef = - G m1 m2 / r2
When the body is at a distance R> Re, for the furthest point (r2) let's call it Rinf
Eo = Ef
½ m1v² - G m1
/ R = - G m1
/ R
v² = 2G
(1 / R - 1 / Rinf)
If we do Rinf = infinity 1 / Rinf = 0
v = √2G
/ R
Ef = = - G m1 m2 / R
The mechanical energy is conserved
Em = -G m1
/ R
Em = - G m1
/ R
R = int ⇒ Em = 0
(6) first choice: the frequency appears higher and wavelength is shorter.
The car approaches a stationary observer and so the sound will appear to have shorter wavelength. This creates an effect of its siren to sound with higher frequency than it would do if both were stationary.
(7) The Doppler formula for frequency in the case of a stationary observer and source approaching it is as follows:

The wavelength is then

The third choice "0.80m; 431Hz" is correct