Answer:
Direct current is used in any electronic device with a battery for a power source. It is also used to charge batteries, so rechargeable devices like laptops and cell phones
Explanation:
I'm not too sure but I think it's nuclear decay
Helium has an atomic mass of 4.00 atomic mass units.
The rotational speed of the person is 0.4 rad/s.
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Rotational speed (rad/s)</h3>
The rotational speed of the person in radian per second is calculated as follows;
v = ωr
where;
- v is linear speed in m/s
- r is radius in meters
- ω is speed in rad/s
ω = v/r
ω = 2/5
ω = 0.4 rad/s
Thus, the rotational speed of the person is 0.4 rad/s.
Learn more about rotational speed here: brainly.com/question/6860269