Question

9
what is the acceleration of a car that accelerates from 0 to 60m/s in 10 seconds?
4 m/s² green
5 m/s² purple
6 m/s² red
10
a race car accelerates from 0m/s to 18m/s in 2 seconds. what is its acceleration?
5 m/s² pink
9 m/s² blue
7 m/s² brown
11
a roller coaster car slows down as it approaches the end of the ride. as it enters the final stretch, its speed is 24 m/s. but 4 seconds later, at the end of the ride, its speed is 8 m/s. what is its average acceleration?
4 m/s² blue
-6 m/s² yellow
-4 m/s² orange
12
in a storm, the wind is blowing with a velocity of 12 m/s. in 4 seconds, the wind’s velocity becomes 6 m/s. what is the wind’s acceleration?
5 m/s² blue
-1.5 m/s² yellow
3 m/s² pink

Explanation:

Problem 9 (Car Acceleration)

Step1: Recall acceleration formula

Acceleration \( a = \frac{\Delta v}{\Delta t} \), where \( \Delta v = v_f - v_i \), \( v_i = 0 \, \text{m/s} \), \( v_f = 60 \, \text{m/s} \), \( \Delta t = 10 \, \text{s} \).

Step2: Calculate \( \Delta v \)

\( \Delta v = 60 - 0 = 60 \, \text{m/s} \).

Step3: Compute acceleration

\( a = \frac{60}{10} = 6 \, \text{m/s}^2 \).

Step1: Use acceleration formula

\( a = \frac{\Delta v}{\Delta t} \), \( v_i = 0 \, \text{m/s} \), \( v_f = 18 \, \text{m/s} \), \( \Delta t = 2 \, \text{s} \).

Step2: Find \( \Delta v \)

\( \Delta v = 18 - 0 = 18 \, \text{m/s} \).

Step3: Calculate acceleration

\( a = \frac{18}{2} = 9 \, \text{m/s}^2 \).

Step1: Recall acceleration formula

\( a = \frac{\Delta v}{\Delta t} \), \( v_i = 24 \, \text{m/s} \), \( v_f = 8 \, \text{m/s} \), \( \Delta t = 4 \, \text{s} \).

Step2: Compute \( \Delta v \)

\( \Delta v = 8 - 24 = -16 \, \text{m/s} \) (negative for deceleration).

Step3: Find acceleration

\( a = \frac{-16}{4} = -4 \, \text{m/s}^2 \).

Answer:

\( 6 \, \text{m/s}^2 \) (Red)

Problem 10 (Race Car Acceleration)