Answer:
R = 0.21 Ω
Explanation:
the formula:
R = r x l/A
R = (44 x 10-⁸ Ωm) x 1.5 / (π x (1 x 10-³ m)²)
R = 6.6 x 10-⁷ / 3.14 x 10-⁶
R = 0.21 Ω
Answer:
420J
Explanation:
Power is the time rate of change in energy. Power is the ratio of energy to time. The S.I unit of power is in watts.
Given that the flash lasts for 1/675 s, power output is 2.7 * 10⁵ W. Hence:
Power = Energy / time
Substituting:
2.7 * 10⁵ W = Energy / (1/675)
Energy = 2.7 * 10⁵ W * 1/675 = 400J
Therefore the energy emitted as light is 400J.
Since the conversion of electric energy to light is 95% efficient, hence the energy stored as electrical energy is:
Energy(capacitor) = 5% of 400J + 400J = 0.05*400 + 400
Energy(capacitor) = 420J
Answer:
it can be calculated by measuring the final distance away from a point, and then subtracting the initial distance
Answer:
699.67ft
Explanation:
We are given with,
- α = 1.2×10⁻⁵ / °C
- L₀ = 700 ft
- ΔT = -10°C − 30°C = -40°C
Now, We have to find ΔL:
- ΔL = (1.2×10⁻⁵ / °C) (700 ft) (-40°C)
- ΔL = −0.336
Rounded to two significant figures, the change in length is −0.33ft.
<u>Therefore, the final length is approximately 700 ft − 0.33 ft = 699.67ft</u>.
Answer: Macroscoptic Output
Explanation:
Answers to the rest:
1. B) macroscopic outputs.
2.A) a microscopic change creating a macroscopic output
3.B) Because the energy levels of the electrons in different metals are usually not the same, different metals usually emit different colors of visible light.
4.A) Heat is applied to a solid, causing its molecules to move quickly.
5.A) strontium, sodium, copper, potassium