1) a charge at rest produces electric feild only but charge in motion produces electric and magnetic feild only

 

2)the current flows along the direction of +ive charge and opp. to direction of -ive charge

 

3)In the case of pipe carrying a cuurent , M. feild  reside outside only but in case of rod it resides outside and inside

 

4)wen a charge enters uniform M.F. , it follows a............

 

a)strt. line path wen B is ll to V i.e theta = 0 or 180

 

b)circular path wen B is perp. to V

 

c)helical wen B is at some arbitary angle to v

i.e theta is not = to 0 , 90 or 180

 

5)a proton , dutron and an alpha particle enters a uniform MF making an angle 90 to the direction of M.F. the ratio of radius of path followed by them wen....

 

a)they have same kinetic energy = 1:(2)^1/2 :1

 

b) they hav = potential diff. = 1 : root 2 : root 2

 

c)= momentum = 2 : 2 : 1

 

thank u

 

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