Answer: I= 0.583A
R=205.83ohms
Explanation: Power= I*V
Where I= current and V = potential difference
I=P/V
I= 70/120
I=0.583A
To find resistance
Using ohms law
V= IR
R=V/I
R= 120/0.583
R= 205.83ohms
Answer
given,
distance = 140 m
time, t = 3.6 s
moving speed = 53 m/s
a) distance = (average velocity) x time
v₀ + 53 = 77.78
v₀ = 24.78 m/s or 25 m/s
b) 
a = 7.8 m/s²
using equation of motion
v₀² = v₁² + 2 a s
53² = 0²+ 2 x 7.8 x s
s = 180 m
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Answer: a) 0.78 m/s b) 1.57 m/s
Explanation:
M = father's mass
m = son's mass = M/3
V = father's initial speed
v = son's initial speed
(1/2)MV^2 = (1/2)*(1/2)*m v^2
M*V^2 = (1/2)(M/3)v^2
V^2/v^2 = 1/4
V = v/2
Second equation:
(1/2)M*(V + 1.4)^2 = (1/2)m*v^2
= (1/2)*(M/3)*(3V)^2
cancel out the M's and (1/2)'s
(V + 1.4)^2 = 3V^2
V^2 + 2.8V + 1.96 = 3V^2
V^2 -1.4V -0.98 = 0
V^2 = 0.98/0.4 = 2.45
V = 1.57
Batteries supply electrons to the circuit by releasing negatively charged atoms or ions. These ions are produced by the batteries through a chemical reaction that spontaneously occurs within the battery. So the negative end of the battery pushes the ions towards the positive end of the circuit with the help of the voltage. This is why eventually, batteries "run out" when the electrode is used up and the chemical reaction can no longer continue.
