To solve for the force applied by the friend, we can use Newton's Second Law of Motion. Newton's Second Law states that the force applied on an object is equal to the mass of the object multiplied by its acceleration:

$F = m \cdot a$

where:

• $F$ is the force,
• $m$ is the mass, and
• $a$ is the acceleration.

Given:

• Mass ($m$) = 50 kg,
• Acceleration ($a$) = 5 m/s².

Plugging in the values:

$F = 50 \, \text{kg} \cdot 5 \, \text{m/s}^2$

$F = 250 \, \text{N}$

So, the force applied by the friend is 250 Newtons (N).

Would you like more details or have any questions? Here are some related questions to expand your understanding:

1. What is Newton's Second Law of Motion, and how is it applied in different scenarios?
2. How does mass affect the acceleration of an object if the same force is applied?
3. What units are used to measure force, mass, and acceleration?
4. How can you determine the mass of an object if you know the force applied and the acceleration?
5. What happens to the acceleration if the mass of the skater is doubled while applying the same force?
6. How do friction and air resistance affect the force needed to accelerate an object?
7. Can you give an example of a situation where Newton's First Law of Motion applies?
8. What are some real-life applications of Newton's Third Law of Motion?

Tip: Always remember to keep track of units when performing calculations in physics to ensure accuracy.