A $75kg$ skateboarder $($including the skateboard$)$ wants to figure out how fast he needs to be traveling at the top of a loop in order to complete the loop! Answer all questions for the case under which he just barely loses contact with the loop as he reaches the top as shown Neglect drag and the size of the skateboarder.

Number of forces

Force$($s$)$ towards center:

Are all forces balanced?

What is the radius of curvature of the path?

What is the centripetal net force on the skateboarder?

What is the skateboarder's centripetal acceleration?

What is the skateboarder's speed?

Would the skateboarder remain in contact with the loop if he reached the top at speed of $4\frac{m}{s}?$