I don't think so. How are you supposed to write the answer?
Answer:1). Distance of far point x=0.9m
Therefore, since the image is virtual
-f=-x = -0.9m
Power of the concave lenses = 1/f = 1/-0.9
= -1.11D
2 ) near point is 21cm = 0.21m
Power = 4-1/near point
= 4/0.21
= 14.2D.
Answer:
7.2 cm
Explanation:
magnetic field, B = 0.301 T
speed, v = 7.92 x 10^5 m/s
mass, m = 4.39 x 10^-27 kg
q = 1.6 x 10^-19 C
The radius of singly changed ion is given by

where, m is the mass of ion, v be the speed of ion, B is the magnetic field and q be the charge

r = 0.072 m
r = 7.2 cm
To solve this problem, we are going to use the formula for
work which is Fd where x and y are measured separately.
X direction: W = 13.5 x 230 = 3105 Joules
Y direction: W = -14.3 x -165 = 2360 Joules
So the total work is getting the sum of the two: 3105 + 2360
= 5465 Joules