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I love physics, but I hate moving. In Motion: A Physics Unit. Rearranging equations: Used to find an unknown value. Goal is to get only the unknown alone on one side of the equation. One rules for moving variables around:.
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I love physics, but I hate moving. In Motion: A Physics Unit
Rearranging equations: • Used to find an unknown value. • Goal is to get only the unknown alone on one side of the equation. • One rules for moving variables around: “Moving a variable ACROSS the equal sign CHANGES the OPERATION.”
Move variables that are multiplied or divided: “Moving ACROSS the equal sign CHANGES the OPERATION.” H 4 = 2 V1 V2 = T1 T2 2 x 4 = H 8 = H
Move variables that are added or subtracted: “Moving ACROSS the equal sign CHANGES the OPERATION.” 4 = x - 2 V1 + a d - a = f 4 + 2 = x 6 = x
(T) (a)(F) P 2x - T + T P = =
8 4 = y = x + b m A y – b = mx A x 4 = 8 y – b = m A = 8 = 2 x x 4 m = y – b
Speedis how fast an object moves. Speed is scalar. It has a size but no direction. The symbol for speed is v The units of speed can be km/h OR m/s or cm/min
v = Δd t Speedis calculated as the total distance travelled over the total timeit took to travel This is actually the average speed. distance time interval
If you travel from Winnipeg to Flin Flon, a distance of 700 km in 7 hours, your speed is? Δd 700 km v = v = t 7 h v= 100 km/h
How long did it take a person driving 50 km/h to go a distance of 300 km? v = 50 km/h Δd v = Δd = 300 km t t = ? t x v = Δd t = 300 km v 50 km/h t = Δd t = 6 h
A skate boarder moves at a speed of 5 m/s, how far does he go in 1 hour? v = 5 m/s Δd = ? t = 1 h Your units always have to match. 60 s 60 min 1 h = 3600 s x x 1 h 1 min Δ d Δd 3600 x 5 = v = t 3600 Δd = 18000 m
Velocitymeasures a change in position with time. Velocity is a vector quantity. (SPEED is total distance over time) v= d t Velocity is calculated as displacement over time.
If you travel from Winnipeg to The Pas, displacement of 420 km [south]. The trip takes 4.00 hours. Velocity is: v = d t 420 km[south] v = 4.00 h v = ? ∆d = 420 km [s] ∆t = 4.0 hr 105 km/h[south]
A car with a velocity of 20 m/s north, traveled for 60 seconds, what was the displacement? Δd v = 20 m/s [N] v = t ∆d = ? ∆t = 60 s t x v = Δd ∆d = 1200 m [N] ∆d = 60 s x 20 m/s [N]
If the stickman below takes 2 seconds to walk, calculate distance, displacement, speed, velocity: 11 cm ∆t = 2 s 6 cm Δd = 11 + 6 + 11Δd = 28 cm ∆d = d2 - d1∆d = 6 cm - 0 cm ∆d = 6 cm (down)
11 cm Δd = 28 cm 6 cm t = 2 s ∆d = 6 cm (down) v = Δd v = d t t v = 6 cm (down) v = 28 cm 2 s 2 s v = 3 cm/s (down) v = 14 cm/s
v = Δd v = d t t d = d2 - d1 t = t2 - t1