An elevator is moving upward with a speed of 11 m/s. Three seconds later, the elevator is still moving upward, but its speed has been reduced to 5.0 m/s. What is the average acceleration of the elevator during the 3.0 s interval?
a.5.3 m/s2, upward
b.2.0 m/s2, upward
c.5.3 m/s2, downward
d.2.7 m/s2, downward
e.2.0 m/s2, downward
its e.2.0 m/s2, downward
Well, well, well, it seems like the elevator is going through quite the journey! To find the average acceleration, we'll need to calculate the change in velocity and divide it by the time interval.
The initial velocity is 11 m/s, and after 3 seconds, it goes down to 5.0 m/s. So, the change in velocity is 11 m/s - 5.0 m/s = 6.0 m/s.
To get the average acceleration, we divide the change in velocity by the time interval:
Average acceleration = (6.0 m/s) / (3.0 s) = 2.0 m/s².
Now, let me put on my thinking cap... or my funny hat! The correct answer is (b) 2.0 m/s² upward. Get ready to elevate your knowledge!
To find the average acceleration, we can use the equation:
average acceleration = change in velocity / time interval
In this case,
initial velocity (u) = 11 m/s
final velocity (v) = 5.0 m/s
time interval (t) = 3.0 s
The change in velocity can be calculated by subtracting the initial velocity from the final velocity:
change in velocity = final velocity - initial velocity = v - u
Plugging in the given values:
change in velocity = 5.0 m/s - 11 m/s = -6.0 m/s
Since the velocity decreased, the acceleration is negative and directed opposite to motion, so it is downward. Therefore, the correct option is:
c. 5.3 m/s², downward
To find the average acceleration of the elevator during the 3.0 s interval, we can use the formula:
average acceleration = (final velocity - initial velocity) / time
Given that the initial velocity is 11 m/s and the final velocity is 5.0 m/s, and the time interval is 3.0 s, we can substitute these values into the formula to find the average acceleration:
average acceleration = (5.0 m/s - 11 m/s) / 3.0 s
Simplifying this expression, we get:
average acceleration = (-6.0 m/s) / 3.0 s
average acceleration = -2.0 m/s²
The negative sign indicates that the acceleration is in the opposite direction to the motion of the elevator. Since the elevator is moving upward, the acceleration is directed downward.
Therefore, the correct answer is option d. 2.7 m/s², downward.