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A Biker slows downHow far does she go when she puts on the brakes?

QuestionA bike rider is going 12 m/s. She puts on her brakes and slows down with 2m/s2. How far (in m) does she go in the next 4 seconds?a. 32; b. 48; c. 64; d.12; 4

Create a step by step solution:SketchCheck units: List the variables we know and want:Pick the physics equation:Algebra:Arithmetic: Letter answer:

v=x/tBasic. (a isnt involved.) If needed, vave=(x-xo)/(t-to); vave=(v+vo)/2a=(v-vo)/tBasic. (x isnt involved.); x=vo*t+at2/2Comes from Eqs. 1&2. Handy if no vv2=vo2+2axComes from Eqs. 3&4. Handy if no t.My solution step by stepSketch

Units OK List the variables we know and want: vo, t, a, x=?Pick the physics equation:

0 tvo=12m/st=4s No v.a=-2m/s/sx=?v=x/ta=(v-vo)/tx=vo*t+at2/2v2=vo2+2ax

voAnswerAlgebra:x=rectangle [vo*t] + triangle [ (v-vo) * t /2]x=vo*t + [ a*t * t/2]6. Arithmetic: x=12*4 +(-2*4*4/2) = 32m7. Answer: a.

voSlope=a

Area=x