Answer:
The energy required to accelerate an electron is 0.582 Mev and 0.350 Mev.
Explanation:
We know that,
Mass of electron 
Rest mass energy for electron = 0.511 Mev
(a). The energy required to accelerate an electron from 0.500c to 0.900c Mev
Using formula of rest,



(b). The energy required to accelerate an electron from 0.900c to 0.942c Mev
Using formula of rest,



Hence, The energy required to accelerate an electron is 0.582 Mev and 0.350 Mev.
Answer:
Diameter will be 351.42 mm
Explanation:
We have given current flowing in the copper wire i = 310 A
Voltage drop across the wire V = 0.55 volt
We know that resistance is given by 
Length of the copper wire l = 1 m
Resisitivity of the copper wire 
We know that resistance 


As area 


So diameter
= 351.42 mm
Freezing point of the water is known as 273 K
Hope this helps!
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You are currently converting Distance and Length units from Centimeters to Feet 321 Centimeters (cm) = 10.5315 Feet (ft) This is a hard one but see if this helps if not let me now and i can try again..