A girl is riding her bicycle. When she gels to a corner, she stops to get a drin

Question

A girl is riding her bicycle. When she gels to a corner, she stops to get a drink from her water bottle. At that time, a friend passes by her, traveling at a constant speed of 8.4 m/s. After 30 s. the girl gets back on her bike and travels with a constant acceleration of 2.0 m/s2. How long does it take for her to catch up with her friend? If the girl had been on her bike and rolling along at a speed of 1.0 m/s when her friend passed, what constant acceleration would she need to catch up with her friend in the same amount of time? Part 1 out of 2 t1 = s

Explanation / Answer

a girl is waited for 30 s and then started

taking the crossing time as reference

the boy will travel a distance of

8.4*(t+30)

girl travelled 1/2*2.0*t2

so both should be equal for them to catch up assuming she didnt shout for him to stop when she was near him

8.4*(t+30)=t2

t2-8.4t=8.4*30

(t-4.2)2=8.4*30+4.22 = 269.64

which gives t = 20.62s

so she will catch him after (30+20.62)s from crossing

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.