Answer:
Explanation:
Since energy is conserved:
2
mu
2
=
2
mv
2
+mgh
⇒u
2
=v
2
+2gh
⇒(3)
2
=v
2
+2(9.8)(0.5−0.5cos60)
⇒v=2m/s
An excited atom can return to its ground state by absorbing electromagnetic radiation is false about the electromagnetic radiation.
Option B
<u>Explanation</u>:
In the scope of modern quantum theory, the term Electromagnetic radiation is identified as the movement of photons through space. Almost all the sources of energy that we utilize today such as coal, oil, etc are a product of electromagnetic radiation which was absorbed from the sun millions of years ago.
Various properties of electromagnetic radiations are a directly proportional relationship between the energy and the frequency, Inverse proportionality between frequency and the wavelength, etc. Hence, we can conclude that an "excited atom" can never return to its ground state by assimilating electromagnetic radiation and the 2nd statement is false.
Answer:
Explanation:
To calculate the time it took the car to hit the ground, we use the formula
speed = distance/time
80 m/s = 300 m/time
time = 300/80
time = 3.75 secs
It must have taken the car 3.75 seconds to hit the ground
To determine the horizontal distance of the car before hitting the ground, the same formula will also be used but with the time obtained above (since that was the time it took before hitting the ground)
speed = distance/time
80 = distance/3.75
distance = 3.75 x 80
distance = 300 meters
