A cart has a mass of $10\,\text{kg}$. A boy applies a horizontal push to the cart with a force of $50\,\text{N}$. The cart has an acceleration of $0.50\,\text{m s}^{-2}$. What is the magnitude of the frictional force acting on the cart?
- A$5.0\,\text{N}$
- B$20\,\text{N}$
- C$30\,\text{N}$
- D$45\,\text{N}$