The lord of the greeks answer d
In some unusual applications of unusual components, I can think of unusual electric circuits where a switch may be connected in parallel with a device in order to control it.
But I'm sure this is not what's intended in a question on the high-school level.
Until you get in a situation with tricky applications in a tricky circuit, your switches will always be connect <em>in series</em> with the devices they control.
Answer:
Change in electric potential energy ∆E = 365.72 kJ
Explanation:
Electric potential energy can be defined mathematically as:
E = kq1q2/r ....1
k = coulomb's constant = 9.0×10^9 N m^2/C^2
q1 = charge 1 = -2.1C
q2 = charge 2 = -5.0C
∆r = change in distance between the charges
r1 = 420km = 420000m
r2 = 160km = 160000m
From equation 1
∆E = kq1q2 (1/r2 -1/r1) ......2
Substituting the given values
∆E = 9.0×10^9 × -2.1 ×-5.0(1/160000 - 1/420000)
∆E = 94.5 × 10^9 (3.87 × 10^-6) J
∆E = 365.72 × 10^3 J
∆E = 365.72 kJ
Answer:
speed of plane in still air = 1060 km/h
speed of wind = 170 km/h
Explanation:
Let teh speed of plane in still air is vp and the speed of air is va.
Irt travels 2670 km in 3 hours against the wind
So,
vp - va = 2670 / 3 = 890 km/h ..... (1)
It travels 11070 km in 9 hours along the wind.
vp + va = 11070 / 9 = 1230 km/h .... (2)
Adding both the equations
2 vp = 2120
vp = 1060 km/h
and va = 1230 - vp = 1230 - 1060 = 170 km/h
