Answer:
<em>it</em><em> </em><em>takes</em><em> </em><em>2</em><em>.</em><em>1</em><em>6</em><em> </em><em>hrs</em><em> </em><em>to</em><em> </em><em>fully</em><em> </em><em>charge</em><em> </em><em>the</em><em> </em><em>phone</em>
Explanation:
V = 5v
I = 1A
E = 38.9 Kj = 38900 j
t = ?
E = IVt
t = E/IV
t = 38900 ÷ (1 × 5)
t = 38900 ÷ 5
t = 7780 seconds
t = 7780/3600............( converting time in seconds to hours)
t = 2.16 hrs
Answer:
b. increasing the number of turns per unit length on the solenoid
e. increasing the current in the solenoid
Explanation:
As we know that energy density depends on the strength of the magnetic field. The magnetic field strength depends on the no of turns of the solenoid and the current passing through it. The greater the number of turns per unit length, greater the current passing through it, more stronger the magnetic field is. As
B = μ₀nI
n = no of turns
I = current through the wire
So the right options are
b. increasing the number of turns per unit length on the solenoid
e. increasing the current in the solenoid
