(A) We can solve the problem by using Ohm's law, which states:
where
V is the potential difference across the electrical device
I is the current through the device
R is its resistance
For the heater coil in the problem, we know
and
, therefore we can rearrange Ohm's law to find the current through the device:
(B) The resistance of a conductive wire depends on three factors. In fact, it is given by:
where
is the resistivity of the material of the wire
L is the length of the wire
A is the cross-sectional area of the wire
Basically, we see that the longer the wire, the larger its resistance; and the larger the section of the wire, the smaller its resistance.
Answer:
Explanation:
wavelength, λ = 2.5 m
speed, v = 13.8 m/s
Amplitude, A = 0.14 m
The general equation of the transverse harmonic wave which is travelling right is given by
where, Ф is phase
At t = 0, x = 0 , y = 0.14 m
0.14 = 0.14 Sin Ф
Ф = π/2
So, the equation is
The wave-particle dual nature of light has been documented and tested many times.
Choice A
120 km/3 hours. 40/1=?/3 1x3=3 hours so 40x3=120 km