Answer:
T= 210.15 N
F= 75.31 N
Explanation:
Let the tension in string be T newton.
According to the question
⇒T×cos21°= mg
⇒T= mg/cos21°
⇒T=20×9.81/cos21
⇒T= 210.15 N
now, the magnitude of horizontal force
F= Tsin21°
⇒F= 210.15×sin21°
=75.31 N
When geophysicists measure the geothermal gradient in areas on the ridges where there is no activity hydrothermally, the gradient is far below than what is predicted theoretically, but when measured near hydrothermal vents it is more than what is predicted. This is because most of the heat is being carried through convection by hydrothermal systems so that the average gradient when measured far from the circulation would be depressed or lower.
Answer:
Photodiodes are used in consumer electronics devices such as compact disc players, smoke detectors, medical devices and the receivers for infrared remote control devices used to control equipment from televisions to air conditioners. For many applications either photodiodes or photoconductors may be used.
Answer:
2.The density of air increases and thendecreases as the sound wave passes.
Explanation:
Sound waves are mechanical waves, which consist of oscillation of the particles in the medium where the wave is transmitted through.
Sound waves are also longitudinal waves, which means that the direction of oscillations of the particles of the medium occurs in a direction parallel to the direction of motion of the wave (so, essentially back and forth).
Due to the nature of longitudinal waves, they create alternating regions of the medium where the density of particles are higher and lower. The former are called compressions, while the latter are called rarefactions.
Therefore, when a sound wave travels through the air, the density of one region of air continuously changes: compression first (high density), rarefaction then (lower density), then compression again, etc..
