Answer:
a) 
b) 
Explanation:
The frequency of the
harmonic of a vibrating string of length <em>L, </em>linear density
under a tension <em>T</em> is given by the formula:

a) So for the <em>fundamental mode</em> (n=1) we have, substituting our values:

b) The <em>frequency difference</em> between successive modes is the fundamental frequency, since:

And.. where is the rest of the question?
Answer: 3 m.
Explanation:
Neglecting the mass of the seesaw, in order the seesaw to be balanced, the sum of the torques created by gravity acting on both children must be 0.
As we are asked to locate Jack at some distance from the fulcrum, we can take torques regarding the fulcrum, which is located at just in the middle of the length of the seesaw.
If we choose the counterclockwise direction as positive, we can write the torque equation as follows (assuming that Jill sits at the left end of the seesaw):
mJill* 5m -mJack* d = 0
60 kg*5 m -100 kg* d =0
Solving for d:
d = 3 m.
Sport and exercise psychology
Explanation:
Here you study the psychological factors that are connected to your performance and contribution to sport, exercises and physical activities.Through application of psychological principles you can attain higher mental health and your performance will be enhanced. For example, you will be able to recognize times when you experience emotional states without without knowing the reasons or causes which is a concept of arousal attribution.Understanding your pattern of behavior and attitude builds up your personality making you distinctive.
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Sports and exercise psychology :brainly.com/question/1213874
Keywords : exercise, sports science, study , achievement motivation, arousal attribution, personal development.
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