Answer:
(a)0.0002778
(b)
Explanation:
(a) The minute hand has a period of 60 minutes ( or 60 * 60 = 3600 seconds) for 1 circle. Its frequency per second would be
1 / 3600 = 0.0002778
(b) The hour hand has a period of 24 hours ( or 24*60 * 60 = 86400
seconds) for 1 circle. Its frequency per second would be
Answer:10m/s
Explanation:
Wave speed ,v=for
Where π= wavelength=2m
Period =1/f f=frequency of wave
F=1/period
=1/0.2=5Hz
So speed of waves,v=5×2=10m/s
Answer: B. meteorites, UV rays
The earth's atmosphere plays an important role in shielding the space rocks and meteorites enters inside the earth due to collision with the celestial body. Due to high heat and pressure in the mesospheric layer of the atmosphere these meteorites burned up before reaching the biosphere or hydrosphere system of the earth. The UV rays are protected from entering into the earth atmosphere by the ozone layer present in the stratosphere of the atmosphere. Both meteorites and UV rays can negatively effect the human population. Therefore, the atmosphere is an agent which provides protection against them.
I believe the answer is D, Heat exhaustion involves a lack of sweating, while heat stroke involves extreme sweating. Also just to add the on if heat exhaustion is left untreated then it could turn into a heat stroke.
