ATAR Notes: Forum

Archived Discussion => 2010 => Mid-year exams => Exam Discussion => Victoria => Physics => Topic started by: madoscar65 on August 29, 2010, 01:22:44 pm

Title: Need help with ticker tape
Post by: madoscar65 on August 29, 2010, 01:22:44 pm: Does anyone know how to find the accerleration on a ticker tape??
Title: Re: Need help with ticker tape
Post by: |ll|lll| on August 29, 2010, 02:30:41 pm: We know that $a=\frac{v-u}{t}$

To find the final velocity, v, take the distance between last 6 dots (5 spaces equivalent) divided by 0.02s x 5.
Likewise, you can take the distance between last 7 dots divided by 0.02s x 6.

To find the initial velocity, u, use the same method as above, but take the distance between the first 6 dots, divided by 0.02s x 5.

Time = t = (Total no. of dots - 1) x 0.02s

Substitute the values into the formula and viola, there your go!

How do we get 0.02 you ask, since the ticker-tape has a frequency of 50 Hertz, it makes 50 dots in one second. Hence, time to make one dot would be $\frac{1}{50}$ s. Time to make say, 6 dots, would be 0.02s x 5. (You don't count the first dot because that's the starting point and there is no distance travelled.)