MCP๋กœ ์—ฐ๊ฒฐ โ†’

๊ณ„์‚ฐ ์ž…๋ ฅ

๊ณต์‹

๊ด‘๊ณ 

๊ฒฐ๊ณผ

์ตœ์ข… ์†๋„
49.05
m/s
๋ณ€์œ„ s 122.63 m
์ตœ์ข… ์†๋„์˜ ์ œ๊ณฑ vยฒ 2,405.9 mยฒ/sยฒ

๋“ฑ๊ฐ€์†๋„ ์šด๋™์ด๋ž€?

๋“ฑ๊ฐ€์†๋„ ์šด๋™์€ ๋ฌผ์ฒด๊ฐ€ ์ผ์ •ํ•œ ๊ฐ€์†๋„๋ฅผ ์œ ์ง€ํ•˜๋ฉฐ ์ง์„  ์œ„๋ฅผ ์›€์ง์ด๋Š” ์šด๋™์„ ๋งํ•ฉ๋‹ˆ๋‹ค. ์ด ์šด๋™์€ ๋‹ค์„ฏ ๊ฐ€์ง€ ๋ฌผ๋ฆฌ๋Ÿ‰ โ€” ์ดˆ๊ธฐ ์†๋„(\(u\)), ์ตœ์ข… ์†๋„(\(v\)), ๊ฐ€์†๋„(\(a\)), ์‹œ๊ฐ„(\(t\)), ๋ณ€์œ„(\(s\)) โ€” ๋กœ ์™„์ „ํžˆ ์„ค๋ช…๋˜๋ฉฐ, ์ด๋“ค์€ ์šด๋™ํ•™์˜ ๊ณ ์ „์ ์ธ SUVAT ๊ณต์‹์œผ๋กœ ์„œ๋กœ ์—ฐ๊ฒฐ๋˜์–ด ์žˆ์Šต๋‹ˆ๋‹ค. ์ด ๊ณ„์‚ฐ๊ธฐ๋Š” ์„ธ ๊ฐ€์ง€ ๊ฐ’ \(u\), \(a\), \(t\)๋ฅผ ์ž…๋ ฅ๋ฐ›์•„ ์ตœ์ข… ์†๋„, ๋ณ€์œ„, ๊ทธ๋ฆฌ๊ณ  \(v^2\) ๊ฐ’์„ ๊ตฌํ•ด ์ค๋‹ˆ๋‹ค.

Velocity versus time graph showing a straight line rising from initial velocity u to final velocity v over time t, with the area beneath shaded.
A velocityโ€“time graph for uniform acceleration: the slope is acceleration a and the shaded area is displacement s.

์‚ฌ์šฉ ๋ฐฉ๋ฒ•

์ดˆ๊ธฐ ์†๋„๋ฅผ ์ดˆ๋‹น ๋ฏธํ„ฐ(m/s) ๋‹จ์œ„๋กœ, ์ผ์ •ํ•œ ๊ฐ€์†๋„๋ฅผ ์ดˆ๋‹น ์ œ๊ณฑ๋ฏธํ„ฐ(m/sยฒ) ๋‹จ์œ„๋กœ, ๊ฒฝ๊ณผ ์‹œ๊ฐ„์„ ์ดˆ(s) ๋‹จ์œ„๋กœ ์ž…๋ ฅํ•˜์„ธ์š”. ๊ณ„์‚ฐ๊ธฐ๊ฐ€ ๊ณง๋ฐ”๋กœ ์ตœ์ข… ์†๋„(\(v\)), ๋ณ€์œ„(\(s\)), ๊ทธ๋ฆฌ๊ณ  \(v^2\)(์ดํ›„ ์ถ”๊ฐ€์ ์ธ ์šด๋™ํ•™ ๊ณ„์‚ฐ์„ ์ด์–ด ๊ฐˆ ๋•Œ ์œ ์šฉํ•ฉ๋‹ˆ๋‹ค)์„ ์ถœ๋ ฅํ•ฉ๋‹ˆ๋‹ค. ๊ฐ์†์„ ๋‚˜ํƒ€๋‚ด๋ ค๋ฉด ๊ฐ€์†๋„์— ์Œ์ˆ˜ ๊ฐ’์„ ๋„ฃ์œผ๋ฉด ๋˜๊ณ , ์ง€ํ‘œ๋ฉด ๊ทผ์ฒ˜์—์„œ ์ž์œ  ๋‚™ํ•˜ํ•˜๋Š” ๋ฌผ์ฒด์—๋Š” \(a = 9.81\)์„ ์‚ฌ์šฉํ•˜์„ธ์š”.

๊ณต์‹ ์„ค๋ช…

์‚ฌ์šฉ๋˜๋Š” ์„ธ ๊ฐ€์ง€ ๊ณต์‹์€ ๋‹ค์Œ๊ณผ ๊ฐ™์Šต๋‹ˆ๋‹ค. $$v = u + a t$$ (์†๋„๋Š” ์‹œ๊ฐ„์— ๋”ฐ๋ผ ์ผ์ •ํ•˜๊ฒŒ ์ฆ๊ฐ€ํ•ฉ๋‹ˆ๋‹ค), $$s = u t + \tfrac{1}{2} a t^2$$ (๋ณ€์œ„๋Š” ์ผ์ •ํ•œ ๋ถ€๋ถ„ \(u t\)์™€ ๊ฐ€์†์— ์˜ํ•œ ๋ถ€๋ถ„ \(\tfrac{1}{2} a t^2\)์ด ํ•ฉ์ณ์ง„ ๊ฐ’์ž…๋‹ˆ๋‹ค), ๊ทธ๋ฆฌ๊ณ  $$v^2 = u^2 + 2 a s$$ (์‹œ๊ฐ„ ์—†์ด ์†๋„์™€ ๋ณ€์œ„๋งŒ์œผ๋กœ ๊ด€๊ณ„๋ฅผ ๋‚˜ํƒ€๋ƒ…๋‹ˆ๋‹ค). ์ด ๊ณต์‹๋“ค์€ ๊ฐ€์†๋„๊ฐ€ ์ผ์ •ํ•  ๋•Œ์—๋งŒ ์„ฑ๋ฆฝํ•ฉ๋‹ˆ๋‹ค.

Diagram of an object moving in a straight line with arrows for initial velocity, final velocity, acceleration and displacement.
The SUVAT quantities: displacement s, initial velocity u, final velocity v, acceleration a over time t.

ํ’€์ด ์˜ˆ์‹œ

ํ•œ ์ž๋™์ฐจ๊ฐ€ \(u = 10\) m/s์—์„œ ์ถœ๋ฐœํ•˜์—ฌ \(a = 2\) m/sยฒ๋กœ \(t = 5\)์ดˆ ๋™์•ˆ ๊ฐ€์†ํ•œ๋‹ค๊ณ  ํ•ฉ์‹œ๋‹ค. ์ตœ์ข… ์†๋„๋Š” $$v = 10 + 2\times 5 = 20 \text{ m/s}$$์ž…๋‹ˆ๋‹ค. ๋ณ€์œ„๋Š” $$s = 10\times 5 + \tfrac{1}{2}\times 2\times 5^2 = 50 + 25 = 75 \text{ m}$$์ด๊ณ , $$v^2 = 10^2 + 2\times 2\times 75 = 100 + 300 = 400 \text{ m}^2/\text{s}^2$$์ด๋ฉฐ, ์ด๋Š” \(20^2\)๊ณผ ๊ฐ™์•„ ๊ฒฐ๊ณผ๊ฐ€ ๋งž๋‹ค๋Š” ๊ฒƒ์„ ํ™•์ธํ•  ์ˆ˜ ์žˆ์Šต๋‹ˆ๋‹ค.

์ž์ฃผ ๋ฌป๋Š” ์งˆ๋ฌธ

๋‹ค๋ฅธ ๋‹จ์œ„๋ฅผ ์‚ฌ์šฉํ•ด๋„ ๋˜๋‚˜์š”? ๊ณ„์‚ฐ ์ž์ฒด๋Š” ๋‹จ์œ„์— ๊ตฌ์• ๋ฐ›์ง€ ์•Š์ง€๋งŒ, ๋‹จ์œ„๋ฅผ ์ผ๊ด€๋˜๊ฒŒ ์จ์•ผ ํ•ฉ๋‹ˆ๋‹ค. ์˜ˆ๋ฅผ ๋“ค์–ด ํ”ผํŠธ์™€ ์ดˆ๋ฅผ ์“ฐ๋ฉด ๊ฒฐ๊ณผ๋„ ํ”ผํŠธ์™€ ํ”ผํŠธ/์ดˆ ๋‹จ์œ„๋กœ ๋‚˜์˜ต๋‹ˆ๋‹ค.

๊ฐ€์†๋„๊ฐ€ 0์ด๋ฉด ์–ด๋–ป๊ฒŒ ๋˜๋‚˜์š”? ๊ณต์‹์€ ๊ทธ๋Œ€๋กœ ์„ฑ๋ฆฝํ•ฉ๋‹ˆ๋‹ค. \(v = u\), \(s = u t\)๊ฐ€ ๋˜์–ด ๋“ฑ์† ์šด๋™์„ ๋‚˜ํƒ€๋ƒ…๋‹ˆ๋‹ค.

๊ฐ์†์€ ์–ด๋–ป๊ฒŒ ๋‚˜ํƒ€๋‚ด๋‚˜์š”? ๊ฐ€์†๋„์— ์Œ์ˆ˜ ๊ฐ’์„ ์ž…๋ ฅํ•˜๋ฉด ๋ฉ๋‹ˆ๋‹ค. ์˜ˆ๋ฅผ ๋“ค์–ด \(-3\) m/sยฒ์„ ๋„ฃ์œผ๋ฉด ๋ฌผ์ฒด๊ฐ€ ๋А๋ ค์ง‘๋‹ˆ๋‹ค.

์ตœ์ข… ์—…๋ฐ์ดํŠธ: