it's either the first or second choice
The sun is just one of the uncountable stars in the universe, as there are more than billions of galaxies containing billions of stars.
Explanation:
voltage = current × resistance
5.
12 V = 4.2 A × resistance
resistance = 12 V / 4.2 A = 2.857142857... Ohm
FYI :
4.2 A would be a lot for a small electronic device like a CD player. that would be 12×4.2 = 50.4 Watt, and the CD player would get really hot.
6.
120 V = current × 12 Ohm
current = 120 V / 12 Ohm = 10 A
Explanation:
It is given that,
Velocity of the electron,
Magnetic field,
Charge of electron,
(a) Let is the force on the electron due to the magnetic field. The magnetic force acting on it is given by :
(b) The charge of electron,
The force acting on the proton is same as force on electron but in opposite direction i.e (-k). Hence, this is the required solution.