Answer:
(a) surface area of the plate will be equal to 
(b) Charge on the capacitor is equal to 
Explanation:
We have given spacing between the plates d = 0.05 mm = 
Value of capacitance 
(A) Capacitance of a parallel plate capacitor is equal to 
So 

So surface area of the plate will be equal to 
(B) It is given that capacitor is charged by 1.5 volt
So voltage V = 1.5 volt
Charge on the capacitor is equal to 
So 
Answer:
Length of the pendulum will be 3.987 m
Explanation:
We have given time period of the pendulum T = 8 sec
Acceleration due to gravity 
We have to find the length of the simple pendulum
We know that time period of the simple pendulum is given by



So length of the pendulum will be 3.987 m
J.J. Thomson discovered the electron by noticing that a beam of particles could be influenced by an electric or magnetic force.. That is option B.
<h3>What is an electron?</h3>
An electron can be defined as the part of an atom that is negatively charged and is found revolving round the nucleus of an atom.
J.J. Thomson was the scientist that discovered electrons through subjecting two oppositely-charged electric plates around the cathode ray.
He noticed that the particles where deflected by both the magnetic and electric fields.
Learn more about cathode rays here:
brainly.com/question/4441361
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