A mouse is running away from a cat at a speed of 0.75 m/s. At a distance of 1.25 m from his mouse hole, the mouse accelerates at a constant rate until he reaches his hole safely, 0.75 s later. What was the mouse's acceleration during the final 1.25 m of his escape? A) 1.8 m/s² B) 1.2 m/s² C) 4.8 m/s² D) 2.4 m/s² E) 6.4 m/s²

Question

Quizplus · Accepted Answer

We can use the kinematic equation: 
distance = initial velocity*time + 0.5*acceleration*time^2

Initial distance = 1.25 m 
Initial velocity = 0.75 m/s 
Time = 0.75 s

Solving for acceleration:

1.25 = (0.75)*0.75 + 0.5*acceleration*(0.75)^2 
1.25 = 0.5625 + 0.28125*acceleration 
0.6875 = 0.28125*acceleration 
acceleration = 2.446 m/s^2

rounded to 2.4 m/s^2

A Mouse Is Running Away from a Cat at a Speed