Answer:
The speed of the electron is
.
Explanation:
Given that,
The magnitude of electric field, 
The magnitude of magnetic field, B = 0.516 T
Both the magnetic and electric fields are acting on the moving electron. Then, the magnitude of electric field and magnetic field is balanced such that :

or

So, the speed of the electron is
. Hence, this is the required solution.
Answer:
Explanation:
Given
Height of ceiling is 
Initial speed of Putty 
Speed of Putty just before it strike the ceiling is given by
where v=final velocity
u=initial velocity
a=acceleration
s=displacement



time taken by putty to reach the ceiling




Answer:
B) The cosmic background radiation is expected to contain spectral lines of hydrogen and helium, and it does.
Explanation:
A. <span>I .................
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Radiation is the transfer of heat energy through space by electromagnetic radiation. Most of the electromagnetic radiation that comes to the earth from the sun is in the form of visible light. Light is made of waves of different frequencies.