Question

1. dean is slowing down on his skateboards. he starts at a speed of 5.6 m/s and slows to 1.0 m/s over a time of 3.1 seconds. what is deans acceleration? (a=vf - vi/t2 - t1)
2. codys car accelerates from 0m/s to 47 m/s northward in 16 seconds. what is the acceleration of the car? (a=vf - vi/t2 - t1)

10)a plane decelerates from 100 m/s to 20 m/s in 10 seconds. what is its acceleration? (a=vf - vi/t2 - t1)

1. a train starts from rest and accelerates uniformly. after 1.5 minutes, its velocity is 700 m/s. what is the acceleration of the train? (a=vf - vi/t2 - t1)

Explanation:

Step1: Identify the formula

The formula for acceleration is \(A=\frac{Vf - Vi}{T2 - t1}\)

Step2: Solve problem 8

Given \(Vi = 5.6\ m/s\), \(Vf=1.0\ m/s\), \(T2 - t1 = 3.1\ s\)
\(A=\frac{1.0 - 5.6}{3.1}=\frac{- 4.6}{3.1}\approx - 1.48\ m/s^{2}\)

Step3: Solve problem 9

Given \(Vi = 0\ m/s\), \(Vf = 47\ m/s\), \(T2 - t1=16\ s\)
\(A=\frac{47-0}{16}=\frac{47}{16}\approx2.94\ m/s^{2}\)

Step4: Solve problem 10

Given \(Vi = 100\ m/s\), \(Vf = 20\ m/s\), \(T2 - t1 = 10\ s\)
\(A=\frac{20 - 100}{10}=\frac{-80}{10}=-8\ m/s^{2}\)

Step5: Solve problem 11

Convert \(1.5\) minutes to seconds: \(1.5\times60 = 90\ s\), \(Vi = 0\ m/s\), \(Vf = 700\ m/s\)
\(A=\frac{700 - 0}{90}=\frac{700}{90}\approx7.78\ m/s^{2}\)

Answer:

1. \(-1.48\ m/s^{2}\)
2. \(2.94\ m/s^{2}\)
3. \(-8\ m/s^{2}\)
4. \(7.78\ m/s^{2}\)