20. If 4 X 1016 J of energy is released in a nuclear reaction. Calculate the mass defect, Am (2 mark)
(A) 0.22kg (B) 0.44kg (C) 0.66kg (D) 0.88kg​

I found this formula in an old book.

E = m · c²

It may be useful.

c = 3 x 10⁸ m/s

c²  = 9 x 10¹⁶ m²/s²

4 x 10¹⁶ J = m · (9 x 10¹⁶ m²/s² )

m = (4 x 10¹⁶ J) / (9 x 10¹⁶ m²/s²)

m  =  0.44 kg (choice-B)  

the components of a vector are the parts of the vectors that are to each other.

b perpendicular

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