A block hangs at rest from the ceiling by a piece of rope. Consider the forces acting on the block. A block hangs from the ceiling by a spring. Consider the forces acting on the block when it is as rest.

A ball is shot into the air with a spring-loaded cannon. Consider the forces acting on the ball while it is in the air.
A skydiver ( who hasn’t opened his parachute yet) falls at terminal velocity. Consider the forces acting on the skydiver)

Force Present or Absent?
-Gravity
-Spring
-Tension
-Normal
-Friction
-Air Resistance

conservation of mass

mass before something happens = mass afterwards

the design of a ski jumping suit involves a trade-off between giving the skiers lift to get higher jumps and ensuring the skier does not face a lot of drag before the jump itself. an expansive suit may to lift the skier higher, but at the same time, it will also increase the air resistance. higher air resistance as the skier goes down the slope limits the speed of the jump. a big suit also increases the risk of losing balance or control, especially if there's a strong gust of wind. while technologically enhanced suits a lot, clothing is not the only factor in a ski jumper’s success. gathering speed while skiing down the slope, ensuring good speed on the ramp, and maintaining good body posture and form in the air all contribute to a ski jumper's success.