- Gas central heating is used for 5 days, using 102 kWh of energy. If 1 kWh of gas costs 7p, calculate the cost of using the cen
1 answer:
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Answer:
32 km east
Explanation:
In order to find the final position of the balloon, we need to calculate its total displacement.
We have:
- Displacement towards west: 18 km
- Displacement towards east: 50 km
The two vectors are on the same line: this means that we can simply add them together (taking into account the proper direction) to obtain the total displacement.
Taking east as positive direction and west as negative direction, we have:
And since it is positive, it means that the final position of the balloon is 32 km east from its initial position.
Answer:
The angular velocity of the propeller is 2.22 rad/s.
Explanation:
The angular velocity (ω) of the propeller is:
Where:
θ: is the angular displacement = 10.6 revolutions
t: is the time = 30 s
Therefore, the angular velocity of the propeller is 2.22 rad/s.
I hope it helps you!
Answer:
the lowest possible frequency of the emitted tone is 404.79 Hz
Explanation:
Given the data in the question;
S₁ ← 5.50 m → L
↑
2.20 m
↓
S₂
We know that, the condition for destructive interference is;
Δr = ( 2m + ) × λ
where m = 0, 1, 2, 3 .......
Path difference between the two sound waves from the two speakers is;
Δr = √( 5.50² + 2.20² ) - 5.50
Δr = 5.92368 - 5.50
Δr = 0.42368 m
v = f × λ
f = ( 2m + )v / Δr
m = 0, 1, 2, 3, ....
Now, for the lowest possible frequency, let m be 0
so
f = ( 0 + )v / Δr
f = (v) / Δr
we know that speed of sound in air v = 343 m/s
so we substitute
f = (343) / 0.42368
f = 171.5 / 0.42368
f = 404.79 Hz
Therefore, the lowest possible frequency of the emitted tone is 404.79 Hz