A 0.14 kg baseball is pitched at a speed of 35 m/s. If it is hit straight back at the pitcher with a force of 5400N exerted over a time interval of 1.0 millisecond, find:
the distance that the baseball was in contact with the bat (hint, use d = Vave*t)
Vave = 1/2(vi + vf)
Vave = 1/2(35 + 73.6)
Vave = 108.6
d = Vave*t
d = 108.6*0.001
d = 0.1086 m
My teacher says this is wrong, but I don't understand what is wrong about it. Help please?!
one of those two speeds is negative
To find the distance that the baseball was in contact with the bat, you correctly used the formula d = Vave * t, where d is the distance, Vave is the average velocity, and t is the time interval.
You correctly calculated the average velocity (Vave) by adding the initial velocity (vi) and the final velocity (vf) and dividing the sum by 2. Plugging in the values, you obtained Vave = 108.6 m/s.
Then, you multiplied the average velocity by the time interval (t), which you correctly converted to seconds by dividing it by 1000. This gives you the distance, d = 0.1086 m.
The calculation you performed looks correct. However, without further information about your teacher's explanation for why it is wrong, it is difficult to pinpoint the specific issue. It's possible that there might be a mistake in the values or a misunderstanding of the context of the problem.
I would recommend double-checking the given values, making sure that the units are consistent (e.g., using meters for distance and seconds for time), and carefully reviewing any additional instructions or information provided by your teacher. If you're still unsure about the error, you may want to seek clarification from your teacher or discuss the problem with classmates.