Question

If one sprinter runs the 400m in 58 seconds and another can run the same distance in 60 seconds, by how much distance will the faster person win by if they race? (physics question)

Answer 1

so average speed of the runner who does 400 m per 58 seconds = ...?
\[ \frac{400m }{ 58s } = \frac{ xm }{1s }\]
solve for x

Answer 2

then do the same for the guy who does it on 60 sec
then work out the distance the 2nd guy has travelled in 58 sec
minus that figure from 400m
= final answer

Answer 3

is that all makin sense @stephjlamb ?

Answer 4

@Jack1 Kinda, my teacher gave us the equation average velocity= change in postition/change in time, would that equation work for the problem?

Answer 5

yeah, it's kinda already given in that the average velocity is:
Runner 1 - 400m/58 seconds
Runner 2 - 400m/60 seconds

these are both average velocities
if you want to make it easier to use, you can convert the velocities into meters travelled per 1 second, or convert to kilometers per hour or feet / day, but either way it will still be the same velocity

Answer 6

so back to the 2nd runner, his average velocity is 400m per 60 seconds
so how far will he travel in 1 second?

Answer 7

6.7 m?

Answer 8

\[\frac{ 400m }{ 60s } \rightarrow \frac{ x }{ 1s }\]

Answer 9

so 60 seconds divided by 60 = 1 second
therefore
400m divided by 60 = x meters

Answer 10

sorry, my net is laggy, yeah, 6.7 m

Answer 11

so if runner 1 finished the race at 58 seconds, he's a position 400m
what position is runner 2 at at 58 seconds?
how far behind runner 1 is this?

Answer 12

Thats ok you've been a great help! so would i just double 6.7- to 13.4
then subtract 13.4 from 400, so that would be 386.6m, and is that my answer?

Answer 13

perfect, spot on hey

Answer 14

Thank you so much!

Answer 15

all good, yw

Answer 16

@Jack1 I have another question, this other problem says- A wombat runs south in a straight line with an average velocity of 5 m/s for 4 minutes and then with an average velocity of 4 m/s for 3 minutes in the same direction
a.) what is its total displacement- which I got as -1920 m or -1.92 km
b.) What is its average velocity during this time? which the answer the worksheet gave me is -4.57 m/s and I was wondering if you knew how to calculate this?

Answer 17

@Jack1

Answer 18

sorry was doing another q, back now

Answer 19

Its ok I solved it!

Answer 20

sweet
...a wombat, where do u get ur maths books from, down unda store ;D

Answer 21

Lol @Jack1

Answer 22

he he he