45W Charging Math: 4,800mAh Takes 25 Minutes in Theory
A 4,800mAh cell is 18.48Wh. Divide by 45W and you get 25 minutes — yet published full-charge measurements run to roughly double that. Here is the gap, calculated output by output.
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Smartphone Battery Cycles: How Many Years Is 800?
The EU floor is 800 charge cycles with 80% of rated capacity still intact. At 70% battery drain per day, 800 cycles arrives in 3.1 years and 1,500 cycles in 5.9. Here is how to convert the number on the label into years of your own use.
Condensing vs Standard Boilers: 92% Efficiency, 9.8% Less Gas
Condensing boilers list 92% or better heating efficiency against the mid-80s for standard units. Converted at Seoul's 22.5268 won per MJ gas rate, the bill gap narrows to 9.8%.
Monitor Gamut Specs: Coverage vs Volume, and What 100% Means
“DCI-P3 99%” and “sRGB 130%” measure different things. Coverage caps at 100%; area and volume can exceed it. Converted against CIE 1931 areas — sRGB 35.0%, DCI-P3 53.6% — here is how to read either number.
Induction vs Radiant Cooktops: 90% Efficiency and the Real Bill
Induction runs at roughly 90% thermal efficiency, radiant (highlight) hobs at 65-70%. The same cooking costs about 25.6 kWh more per month, worth anywhere from 3,490 to 8,940 won depending on your tariff tier.
DisplayHDR 400 vs 600 vs 1000: The Contrast Ratio Math
DisplayHDR 400 requires no local dimming and allows a black level of 0.4 nits. Divide the certified numbers and the guaranteed floor is just 1,000:1 — while True Black 400 reaches 800,000:1.
IP68 vs IP48: Why Foldables Stop at a Dust Rating of 4
The two digits after IP come from separate tests. Samsung's foldables moved from IPX8 to IP48, where the leading 4 only blocks objects 1mm and larger. Includes the actual water pressure behind a 1.5m immersion test.
Dolby Vision vs HDR10: 12-Bit and Dynamic Metadata Explained
Dolby Vision carries up to 12-bit depth with per-scene dynamic metadata; HDR10 uses 10-bit with a single fixed value for the whole title. In displayable colours that is 68.7 billion against 1.07 billion — 64 times apart.
SSD Endurance: How Long 600TBW Really Lasts at 20GB a Day
Burning a 1TB SSD's 600TBW inside five years takes 329GB of writes a day. At 20GB a day it takes 82 years. Converted to DWPD, every capacity lands on the same 0.33.
TV size and viewing distance: the 4.13 multiplier explained
Multiply the screen diagonal in inches by 4.13 for the recommended distance in centimetres. A 65-inch set wants 268cm at the SMPTE standard and 198cm at the immersive one — which is why the same 2.7m room justifies either 65 or 89 inches.