Answer:
a) The average velocity is 32 m/s
b) See the attached figure. Slope of the line = 32.
Graphic: a line that passes through the points (0; 50) and (5; 210)
Explanation:
a) The average velocity is calculated as the displacement over time:
v = ΔX / Δt
where
ΔX : displacement ( final position - initial position)
Δt : time (final time - initial time)
Considering the origin of the reference system as the position where the observer is:
ΔX = 210 m - 50 m = 160 m
Δt = 5 s
v = 160 m / 5 s = 32 m/s
b) In the graphic position vs time, plot a line that passes through the points (0, 50) (because at time 0, the car is 50 m away from you, the center of the reference system) and (5, 210). The x-axis, time, is in seconds and the y-axis, position, in meters. The slope of the line is calculated as:
slope = (X₂ - X₁) /(t₂ - t₁) = (210 - 50) / (5 - 0) = 32. Then, the velocity is equal to the slope of the line. See the attached figure.
Answer:
The energy of the wave is 1.435 x 10⁻⁴ J
Explanation:
Given;
area of the window, A = 0.5 m²
the rms value of the field, E = 0.06 V/m
The peak value of electric field is given by;
The average intensity of the wave is given by;
The average power of the wave is given by;
P = I x A
P = (9.569 x 10⁻⁶ W/m²) (0.5 m²)
P = 4.784 x 10⁻⁶ W
The energy of the wave is given by;
E = P x t
E = (4.784 x 10⁻⁶ W)(30 s)
E = 1.435 x 10⁻⁴ J
Therefore, the energy of the wave is 1.435 x 10⁻⁴ J
Explanation:
Given that,
Two resistors 4.5 Ω and 2.3 Ω .
Potential difference = 30 V
When they are in series, the current through each resistor remains the same. First find the equivalent resistance.
R' = 4.5 + 2.3
= 6.8 Ω
Current,
So, the current through both lightbulb is the same i.e. 4.41 A.
When they are in parallel, the current divides.
Current flowing in 4.5 resistor,
Current flowing in 2.3 ohm resistor,
In parallel combination, are brighter than bulbs in series.
