Answer:
4.9 eV .
Explanation:
It is the case of discharge through mercury tube light . In it , mercury atoms are exited due to which electrons are sent to higher energy level . Here current drops to zero because electrons are excited to higher level . Energy are absorbed in quantised manner . Energy absorbed by electrons will be 4.9 eV . That means , difference in energy between two energy level is 4.9 eV .
Answer:
It's really important waves type for fulfill human's needs
Explanation:
Electromagnetic waves are transverse waves composed by the perpendicular oscillating electric and magnetic fields.
EM waves have both Electrical and magnetic features.
they travel in the velocity of light (3*10⁸ ms⁻¹)
they does not require any media to travel. It has two perpendicular electric field and the magnetic field which are perpendicular to each other
They travel perpendicular to each of those electric and magnetic fields.
Example :
- Radio Wave
- Micro Wave
- IR wave
- Light Wave
- UV rays
- X rays
- Gamma rays
- Cosmic rays
The main importance of em waves is they allow energy to be stored within them and then can be propagated over a large distance using the dielectric and magnetic properties of materials .
This performance has been used in many fields wisely and effectively to make the things easy.
Ex : medicine , Telecommunication , energy , Engineering etc
<u>Answer:</u>
The final velocity of the two railroad cars is 1.09 m/s
<u>Explanation:</u>
Since we are given that the two cars lock together it shows that the collision is inelastic in nature. The final velocity due to inelastic collision is given by

where
V= Final velocity
M1= mass of the first object in kgs = 12000
M2= mas of the second object in kgs = 10000
V1= initial velocity of the first object in m/s = 2m/s
V2= initial velocity of the second object in m/s = 0 (given at rest)
Substituting the given values in the formula we get
V = 2×12000 + 0x100012000 + 10000= 2400022000= 1.09 m/s

Which is the final velocity of the two railroad cars
Answer:
1.1 V
Explanation:
L = 0.45 m
d = 0.11 m
B = 0.80 T
t = 0.036 s
Let e be the emf.
e = B v L
e = 0.80 x 0.11 x 0.45 / 0.036 = 1.1 V
Answer:
The length is 
Explanation:
From the question we are told that
The frequencies of the two successive harmonics are
, 
The speed of sound in the air is 
Generally the frequency of a given harmonic is mathematically represented as

Here n defines the position of the harmonics
Now since the position of both harmonic is not know but we know that they successive then we can represented them mathematically as

and

So

=> 
=> 