Answer:
this is due to difference in speeds of sound and light
Explanation:
light has a speed of 3×10^8 m/s and it is seen at once because it takes negligible time due to very high speed and short distance that is why as soon as lightning occurs we can see it . since thundering sound travels with speed of sound which is about 330 to 340 m/s in air hence it takes some time as described in question as 6 seconds
Explanation:
Vnet = 0.4m/s - 3.0m/s = - 2.6m/s
so the man walks 2.6m/s towards the west
It’s burning wax. All of the other options are physical changes .
Answer:
Energy cannot be changed from one form to another without a loss of usable energy
Explanation:
Second law of thermodynamics states that the total entropy or the randomness of the system remains constant over time. It also states that the net entropy will remain the same or it will increase.
Entropy of a system is given by heat absorbed divided by temperature. It is given by :

So, the correct option is (A) "Energy cannot be changed from one form to another without a loss of usable energy".
the scientific study of natural forces such as light, sound, heat, electricity, pressure, etc.