You will have to use this formula:
Final Velocity (V) = 4m/s
Initial Velocity (Vo) = 8m/s
Acceleration (a) = ? m/s^2
Time (t) = 2 secs
Then:
-> 4 = 8 + a x 2
-> 4 - 8 = 2a
-> -4 = 2a
-> a = -4/2
-> a = -2 m/s^2
Ps: It's value is negative because the she was in retrograde motion.
Answer: Her acceleration is -2 m/s^2.
<span>It is quite straightforward to convert an uncertainty to a percent uncertainty. We can divide the amount of uncertainty by the original amount and then multiply by 100%.
(2 m / 20,000,000 m) X 100% = 0.00001%
The percent uncertainty is 0.00001%.
The percent accuracy is the 100% - percent uncertainty.
The percent accuracy = 100% - 0.00001% = 99.99999%
The percent accuracy is 99.99999%.</span>
1) The kinetic energy of an object is given by:
where m is the object's mass and v its speed.
By using this equation, we find the initial kinetic energy of the skateboarder:
and the final kinetic energy as well:
So, her change in kinetic energy is
2) The work-energy theorem states that the work done to increase the speed of an object is equal to the variation of kinetic energy of the object:
Therefore, the work done by the skateboarder is
The neutral table tennis ball will become
polarized, with positive charges toward the glass rod. The
correct answer between all the choices given is the last choice or letter D. I
am hoping that this answer has satisfied your query and it will be able to help
you, and if you would like, feel free to ask another question.
When air is blown into the open pipe,
L = 
where nis any integral number 1,2,3,4 etc. and λ is the wavelength of the oscillation
⇒λ=
Note here that n=1 is for fundamental, n=2 is first harmonic and so on..
⇒ third harmonic will be n=4
Given L=6m, n=4, solving for λ we get:
λ=
=3m
Relationship of frequency(f), velocity of sound (c) and wavelength(λ) is:
c=f.λ Or f= 
⇒f=
≈115 Hz
