The correct answer of this question is : A) Change alternating current into direct current.
EXPLANATION :
As per the question, we are given vacuum tube. Vacuum tube can be of various types. Normally it contains two electrodes called cathode and anode which are enclosed in an evacuated glass chamber . There are also other types of vacuum tubes which contain extra electrodes like control grid .
The vacuum tube can be used as a rectifier. It means that it can be used as an electronic device which will convert alternating current into direct current. It may be a half wave rectifier or a full wave rectifier. Actually the direct current obtained during the rectification of alternating current is pulsating in nature.
Hence, the correct answer is that a vacuum tube can be used to change alternating current into direct current.
Answer:
red has a longer wavelength than yellow. Yellow has a longer wavelength than green.
Explanation
in the visible spectrum a color with high frequency contains shorter wavelength.In this case red color has high wavelength followed by yellow followed by green,blue and violet.
Answer:
A colorful interference pattern is observed when light is reflected from the top and bottom boundaries of a thin oil film. The different bands form as the film's thickness diminishes from a central run-off-poin
Explanation:
<h3>hope it help brainliest pls</h3>
Answer:
a). 87.5 mA or 
A
b). 1.78 
Explanation:
n the number of free electrons is 28 in text reference and if they don't give q is take as the charge of electron.
a).
A
b).
Answer:
Her speed at the bottom of the slope is 25.665 m/s
Explanation:
Here we have
Initial velocity, v₁= 15 m/s
Final velocity = v₂
The energy balance present in the system can be represented as
Where:
m = Mass of the cyclist = 70 kg
W = work done by the drag force = 
Where:
d = Distance traveled = 450 m
Therefore,
and
= 658.714 m²/s²
v₂ = 25.665 m/s
Her speed at the bottom of the slope = 25.665 m/s.
