Answer:
The correct option is;
a) Mike, he is within his target heart rate zone
Explanation:
The Target Heart Rate Zone (THRZ) is the range of the percentage of a person's maximal heart beat rate (MHR) targeted to be achieved during exercising. It is a very good way to gauge the comparative intensity of a person's exercise
Whereby, Joe's heart beat rate is below his THRZ and Mikes heart beat rate is within his THRZ, Mike is working harder.
Hence the correct option is (a) Mike, he is within his target heart rate zone.
The object does not move.
<h2>Frequency of trumpet wire = 445 Hz</h2>
Explanation:
The given frequency of tuning fork is 440 Hz . It produces 5 beats with trumpet wire . That means , the frequency of wire can be 440 ± 5
It can be either 445 or 435
Now the length of wire is increased , by which its frequency decreases . Because frequency is inversely proportional to length of wire .
If we decrease the frequency in 435 , the difference between tuning fork frequency and wire frequency will become greater than 5 even . So it cannot produce 3 beats with it .
If we decrease frequency from 445 , it can become 443 Hz . It gives 3 beat with the tuning fork as given .
Thus the initial frequency of wire is 445 Hz
Yes. It's approximately the same, but not exactly.
The weight of an object 7 miles above the Earth's surface (the gravitational force on it) is about 0.35% less than it is down on the surface.