Answer:
See the answers below.
Explanation:
The total power of the circuit is equal to the sum of the powers of each lamp.
![P=60+100\\P=160 [W]](https://tex.z-dn.net/?f=P%3D60%2B100%5C%5CP%3D160%20%5BW%5D)
Now we have a voltage source equal to 240 [V], so by means of the following equation we can find the current circulating in the circuit.

where:
P = power [W]
V = voltage [V]
I = current [amp]
![I = P/V\\I=160/240\\I=0.67 [amp]](https://tex.z-dn.net/?f=I%20%3D%20P%2FV%5C%5CI%3D160%2F240%5C%5CI%3D0.67%20%5Bamp%5D)
So this is the answer for c) I = 0.67 [amp]
We know that the voltage of each lamp is 240 [V]. Therefore using ohm's law which is equal to the product of resistance by current we can find the voltage of each lamp.
a)

where:
V = voltage [V]
I = current [amp]
R = resistance [ohms]
Therefore we replace this equation in the first to have the current as a function of the resistance and not the voltage.

![60 = (0.67)^{2}*R\\R_{60}=133.66[ohm] \\and\\100=(0.67)^{2} *R\\R_{100}=100/(0.66^{2} )\\R_{100}=225 [ohm]](https://tex.z-dn.net/?f=60%20%3D%20%280.67%29%5E%7B2%7D%2AR%5C%5CR_%7B60%7D%3D133.66%5Bohm%5D%20%5C%5Cand%5C%5C100%3D%280.67%29%5E%7B2%7D%20%2AR%5C%5CR_%7B100%7D%3D100%2F%280.66%5E%7B2%7D%20%29%5C%5CR_%7B100%7D%3D225%20%5Bohm%5D)
b)
The effective resistance of a series circuit is equal to the sum of the resistors connected in series.
![R = 133.66 + 225\\R = 358.67 [ohms]](https://tex.z-dn.net/?f=R%20%3D%20133.66%20%2B%20225%5C%5CR%20%3D%20358.67%20%5Bohms%5D)
Answer:
1 hour to ride his motorcycle
Answer:
f = 130 Khz
Explanation:
In a circuit driven by a sinusoidal voltage source, there exists a fixed relationship between the amplitudes of the current and the voltage through any circuit element, at any time.
For an inductor, this relationship can be expressed as follows:
VL = IL * XL (1) , which is a generalized form of Ohm's Law.
XL is called the inductive reactance, and is defined as follows:
XL = ω*L = 2*π*f*L, where f is the frequency of the sinusoidal source (in Hz) and L is the value of the inductance, in H.
Replacing in (1), by the values given of VL, IL, and L, we can solve for f, as follows:
f = VL / 2*π*IL*L = 12 V / 2*π*(3.00*10⁻³) A* (4.9*10⁻³) H = 130 Khz
yes
evaporation starts on the surface
Answer:
T = 0.00889 N*m
Explanation:
Given the initial speed
Vo = 9.0rev/s.
V = 65 rev/10s
V = 6.5 rev/s.
V = Vo + a*t
Solve to acceleration knowing the initial velocity and the velocity at 10 s
6.5 rev/s - 9 rev/s = a*10s
a = -0.25 rev/s^2.
Now the solve the time at stop time so V=0
V = Vo + a*t
0 = 9.0 - 0.25 rev/s *t,
t = 36 s The Stopping time.
36s - 10s = 26s
The torque can be find using the acceleration using the equation
T = I*a
I = 1/2*m*r^2
I = 1/2*0.725kg*(0.315m)^2= 0.0359kg*m^2
T = 0.0359kg*m^2*-0.25rev/s^2
T = 0.00889 N*m