Answer: The energy from the sun passes through space in the form of invisible waves to the earth surface. It heats up the earth’s surface causing variation in climate.
Explanation:
The amount of incoming energy from the Sun decides the weather and climate of earth. If the energy that is incoming and outgoing on the earth, then climate is in equilibrium. The balance is depending on the scattering, absorption, reflection and transformation of energy.
The energy from sun passes through space and reaches the earth’s surface. On reaching surface, the solar energy warms the atmosphere releasing heat energy which gets transferred throughout the planets system by radiation, conduction and convection. Conduction happens in the atmosphere within first several millimeters close to the surface. This heated air expands as it is dense and rises causing transfer of heat to atmosphere through convection process. It results in formation of clouds.
The radiant energy from sun is transmitted via space in form of invisible waves. But much of the suns radiant energy, is transmitted back to atmosphere. The objects on earth like land, plants, animals absorb radiant energy as heat of which one third gets re-radiated back to atmosphere that is absorbed by carbon dioxide and water vapor. The atmosphere radiates heat energy back to earth increasing the earth temperature. This trapping of radiation is greenhouse effect.
The thermal energy obtained by convection currents are responsible for wind, cloud formation, and weather formation. The hydrosphere that comprises of 70% of earth’s surface absorbs solar energy.
On the basis of the above explanation is:
The energy from the sun passes through space in the form of invisible waves to the earth surface. It heats up the earth’s surface causing variation in climate.
B. A pot of boiling water represents a system that is completely open.
Answer:
(B) at the middle of the pipe
Explanation:
In the case of an open pipe which vibrates in fundamental mode, an anti-node is formed at the middle of the pipe, here the amplitude of the wave is maximum. Hence, the pressure variation is also maximum at the middle.
Using the cosine rule (a^2 = b^2 + c^2 - 2bc cos A), we can work out the displacement:
Displacement = a
b = 30
c = 50
A = 180 - 35 = 145 degrees.
a^2= 900 + 2500 -1500*-0.81915...
= 3400 + 1228.728...
= 4628.72...
a = 68.034...
= 68.0m (to 3s.f.).
To work out the angle from starting place, use another configuration of the cosine rule:
:
cos (C)=
= 3028.7.../4080
= 0.7423...
C = 42.069... degrees
= 042 bearing
