Answer:
I think electricity is one kind of energy
Answer:
Explanation:
T₁ = 700 + 273 = 973 k
T₂ = 330 + 273 = 603 k
Theoretical efficiency = T₁ - T₂ / T₁
= (973 - 603) / 973
= .38 OR 38%
Operating efficiency = .79 x 38
= 30.02 %
Heat input Q₁ , Heat output to sink Q₂ , conversion into power = Q₁ - Q₂
given Q₁ - Q₂ = 1.3 x 10⁹ W
efficiency = Q₁ - Q₂ / Q₁
Q₁ - Q₂ / Q₁ = 30.02 / 100
100Q₁ - 100Q₂ = 30.02Q₁
69.98 Q₁ = 100Q₂
Q₁ = 1.429 Q₂
Putting this in the relation
Q₁ - Q₂ = 1.3 x 10⁹ W
1.429Q₂ - Q₂ = 1.3 x 10⁹ W
.429Q₂ = 1.3 x 10⁹
Q₂ = 3.03 x 10⁹W
= 3.03 GW.
Answer:
All of the following devices transmit energy/information: cell phones, walkie talkies, remote controls, and sunlight.
They are all radiation.
I got a 100 on this test.
1. consider the free body diagram. If the sum of the tension forces is equal to the force of gravity, which description BEST applies?
answer. A girl hangs by both hands, motionless, from a trapeze.
2. What causes sea floor spreading ?
answer. Magma.
3. 10 n -> (BOx) <- 20 n Which expression represents the total force on the block ?
answer. 10n =+ -20n.
4. Which waves move by replacing one particle with another?
answer. Sound waves.
5. The table shows dates and appearance of index fossils. Which rock layers can be dated most precisely?
answer. a layer containing both a fossil from 1 and 2
This is an illustration of the ___ moon
answer. new.
hope these help
Answer:
8.6 m/s
Explanation:
The observer is stationary
The source is moving
Let v₀ be the speed of sound in the air
Let v be the speed of the ambulance
As the siren approaches
f₁ = 2000(v₀ / (v₀ - v))
As the siren departs
f₁' = 2000(v₀ / (v₀ + v))
f₁ - f₁' = 100
2000(v₀ / (v₀ - v)) - 2000(v₀ / (v₀ + v)) = 100
v₀ / (v₀ - v) - v₀ / (v₀ + v) = 100/2000
v₀(v₀ + v) / (v₀ - v)(v₀ + v) - v₀(v₀ - v) / (v₀ - v)(v₀ + v) = 0.05
(v₀² + vv₀) - (v₀² - vv₀) / (v₀² - v²) = 0.05
2vv₀ / (v₀² - v²) = 0.05
2vv₀ = 0.05 (v₀² - v²)
0.05v² + 2vv₀ - 0.05v₀² = 0
v² + 40vv₀ - v₀² = 0
quadratic formula positive answer
v = (-40v₀ + √((40v₀)² - 4(1)(v₀²))) / 2
v = (-40v₀ + √(1604v₀²)) / 2
v = (0.049968v₀) / 2
v = 0.02498439v₀
If we assume the speed of sound in air is 343 m/s
v = 8.56964... = 8.6 m/s
Approaching frequency heard is 2051 Hz
Departing frequency heard is 1951 Hz