Since the bulb consumes 100 watts of power and its efficiency is 95%,
it generates 95 watts of light energy and 5 watts of heat energy whenever
it's turned on.
5 watts means 5 joules of energy per second.
(2.5 hours) x (3,600 seconds/hour) = 9,000 seconds
(9,000 seconds) x (5 joules/second) = 45,000 joules of heat in 2.5 hours
Force exerted by the bullet = mass * acceleration = 0.013 * 850 = 11.05 Newtons.
the rifle exerts same force in opposite direction so we have
11.05 = 3.5 * a
acceleration = 11.05 / 3.5 = 3.16 m /s^-2
Answer
given,
net charge = +2.00 μC
we know,
1 coulomb charge = 6.28 x 10¹⁸electrons
1 micro coulomb charge = 6.28 x 10¹⁸ x 10⁻⁶ electron
= 6.28 x 10¹² electrons
2.00 μC = 2 x 6.28 x 10¹² electrons
= 1.256 x 10¹³ electrons
since net charge is positive.
The number of protons should be 1.256 x 10¹³ more than electrons.
hence, +2.00 μC have 1.256 x 10¹³ more protons than electrons.