Concept:
The centripetal force required to keep an object moving in a circular path is given by
\[
F = \frac{mv^2}{r}
\]
where
\(m\) = mass,
\(v\) = velocity,
\(r\) = radius of the circular path.
Step 1: Substitute the given values.
\[
m = 1000\,\text{kg}, \quad v = 20\,\text{m/s}, \quad r = 50\,\text{m}
\]
\[
F = \frac{1000 \times (20)^2}{50}
\]
Step 2: Simplify the expression.
\[
F = \frac{1000 \times 400}{50}
\]
\[
F = \frac{400000}{50}
\]
\[
F = 8000\,\text{N}
\]