Option (B) is correct.The magnetic field strength=8.5 x 10² T
Explanation:
the magnetic force Fm is given by
Fm= q V B sinθ
q= charge=1.4 x 10⁻⁷ C
v= velocity= 1.3 x 10⁶ m/s
B= magnetic field strength
Fm= magnetic force= 1.5 x 10² N
θ=75°
so 1.5 x 10²=(1.4 x 10⁻⁷) (1.3 x 10⁶ ) (B) sin75
B=8.5 x 10² T
(89000/102000)×100
=87.25%
(92000/104000)×100
=88.46%
efficiency is (output/input)×100
if u get confused which way input and output should go, remember the smaller value is always output and it's above in the fraction, then only it's possible to get a efficiency lower than 100.
The size of the force varies inversely as the square of the distance between the two charges. Therefore, if the distance between the two charges is doubled, the attraction or repulsion becomes weaker, decreasing to one-fourth of the original value
Both have positive charge. In fact, an alpha particle IS a nucleus of a Helium atom.