The process in which water vapor and
carbon dioxide retain heat is called the greenhouse effect.
<span>There are many gases which causes greenhouse
effect like carbon dioxide, methane, nitrous oxide, fluorinated gases etc. These
gases trap the heat in the atmosphere, resulting the surface of earth to get
warm producing greenhouse effect.</span>
Answer:The frequency of the echo is slightly decreased
Explanation:
Given
speed of boat 
cliff is
away
when boat is still , suppose t is the time taken by the echo to reach observer on the boat
But as soon as boat starts moving the distance between cliff and boat decreasing and time for echo to reach observer also decreases
and we know 
therefore frequency of the echo slightly decreased.
Answer:
Explanation:
given,
tuning fork vibration = 508 Hz
accelerates = 9.80 m/s²
speed of sound = 343 m/s
observed frequency = 490 Hz


![v_s = v[\dfrac{f_s}{f_o}-1]](https://tex.z-dn.net/?f=v_s%20%3D%20v%5B%5Cdfrac%7Bf_s%7D%7Bf_o%7D-1%5D)
![= 343[\dfrac{508}{490}-1]](https://tex.z-dn.net/?f=%3D%20343%5B%5Cdfrac%7B508%7D%7B490%7D-1%5D)

distance the tunning fork has fallen


=8.1 m
now, time required for the observed will be

now, for the distance calculation


=0.293 m
total distance
= 8.1 + 0.293 = 8.392 m
Answer: True
Explanation: Inductors are similar to resistors, due to the fact that they offer resistance to current flow, but Inductors are different from resistors in that, while resistors loss electric energy in a circuit in the form of heat, an inductor stores that energy in the form of a magnetic field.
As current passes through an inductor overtime it tends to store current in the form of magnetic field. Therefore the electric-power industry can store energy in large Inductors.