3. Acceleration, a, in meters per second squared (m/5}), is found by the formula a= (V2-V2)/t where V1, is the beginning velocity, V2 is the end velocity, and t is time. What is the acceleration, in m/s², of an object with a beginning velocity of 14 m/s and end velocity of 8 m/s over a time of 4 seconds?
Answer: B
The acceleration of the object is -1.5 m/s².
To find the acceleration, we use the formula a = (V2 - V1) / t. Substituting the values, we get a = (8 m/s - 14 m/s) / 4 s, which simplifies to a = -6 m/s / 4 s, resulting in an acceleration of -1.5 m/s².
A) 1.5
Option A is incorrect because it represents a positive acceleration. The correct calculation shows that the object is actually slowing down, leading to a negative acceleration value of -1.5 m/s².
B) -1.5
Option B is correct as it accurately reflects the calculated acceleration. By substituting the given velocities and time into the formula, we find that the object experiences a decrease in velocity, resulting in -1.5 m/s².
C) 4.5
Option C is incorrect since it does not reflect the change in velocity correctly. The calculation indicates a deceleration, and thus a positive acceleration of 4.5 m/s² does not align with the values provided.
D) -12
Option D is also incorrect. Although it is a negative value, the calculation from the provided velocities and time does not yield such a large magnitude of acceleration. The correct value from our calculations is -1.5 m/s².
Conclusion
The correct answer is -1.5 m/s² because it accurately represents the deceleration of the object as it slows from 14 m/s to 8 m/s over 4 seconds. All other options fail to reflect both the magnitude and direction of the acceleration based on the provided values.