Question

Can you answer this question?

Brad is working on a speed problem in physics class. The problem tells him that a girl runs from her house to the park 0.05 km away in 10 s. Brad calculates that her speed is 0.005 m/s. Is he correct? If not, explain the flaw or flaws in his problem solving process.

Answer 1

no

Explanation:

`0.05km = 0.05 * 1000m`

`= 50m`

`s = d/t`

where `d` is distance in metres `m`,

`t` is time in seconds `s`,

and `s` is speed in metres per second `m//s`.

here, `d = 50m` and `t = 10s`

`d/t = 50/10`

`s = 5 m//s`

the speed could also be expressed as `0.005 km//s`, but not `5 m//s`;

the number would need to be multiplied by `1000` since the unit `km` was converted to `m`.