Answer: a.
Explanation: i have done this before .. hope this helps (⌐■_■)
<span>The difference between work done by the gravitational force on descending and ascending objects is that for descending objects a terminal velocity will be reached where the object will not fall any faster that it already is. For an ascending object, its velocity will come down the longer gravity has an effect on it until the object begins to descend and the velocity of an ascending object will continue to change the longer gravity has an effect on it.</span>
The radius of curvature of the proton's path while in the field is
×
.
b) Let R = radius curvature of protons path. Then,
relation b/w B, R, and v is: -


× 
Hence, the radius of curvature of the proton's path while in the field is
×
.
<h3>
What do you mean by Magnetic field?</h3>
The magnetic influence on moving electric charges, electric currents and magnetic materials is described by a magnetic field, which is a vector field. A force perpendicular to the charge's own velocity and the magnetic field acts on it when the charge is travelling through a magnetic field. The magnetic field of a permanent magnet pulls on ferromagnetic substances like iron and attracts or repels other magnets. A magnetic field that varies with location will also exert a force on a variety of non-magnetic materials by changing the velocity of those particles' outer electrons. Electric currents, like those utilized in electromagnets, and electric fields that change in time produce magnetic fields that surround magnetized things.
To know more about Magnetic Field visit:
brainly.com/question/14848188
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