A. A 60 kg skier starts from rest atheight H=20 m above the end of a ski-jump ra

Question

A. A60 kg skier starts from rest atheight H=20m above the end of a ski-jump ramp andleaves the ramp at an angle of30o. i. What is the maximum height h ofhis jump above the end of the ramp? ii. If he increased his weightby putting on a backpack, would h then be greater, less or thesame? (Neglect the effects of air resistance and assume theramp is frictionless)
--------------------------------------------------------------------------------------------------------- B. An object of10kg is resting on a spring. The springis compressed 12cm by the stone.
i. What is the spring constant?
ii. The stone is then pushed down anadditional 30cm and released. What is theelastic potential energy of the compressed spring just before thatrelease?
iii.What is the change in thegravitational potential energy of the object- Earth system when theobject moves from the release point to it’s maximumheight? ---------------------------------------------------------------------------------------------------------

Explanation / Answer

. mass of skier m = 60kg
Initial velocity u = 0 Initial height  H=20m angle = 30o. Speed of the skier at end of ramp v = [ 2gH ]                                                      = 19.79 m / s i. the maximum height h of hisjump above the end of the ramp h = ( v sin ) ^ 2/ ( 2g)                                                                                                  = 5 m ii. If he increased his weightby putting on a backpack,height h is the same B. mass of object m =10kg compression of spring x =12cm = 0.12 m
i. the spring constant k = mg /x                                    = 816.66 N / m
ii. addiational compression x' = 30cm =0.3 m the elastic potential energy ofthe compressed spring just before that release = ( 1/ 2) k ( x+ x') ^ 2                                                                                                                   = 72.03 J
iii. the change in the gravitationalpotential energy of the object- Earth system when the object movesfrom the release point to it’s maximum height = 72.03J compression of spring x =12cm = 0.12 m
i. the spring constant k = mg /x                                    = 816.66 N / m
ii. addiational compression x' = 30cm =0.3 m the elastic potential energy ofthe compressed spring just before that release = ( 1/ 2) k ( x+ x') ^ 2                                                                                                                   = 72.03 J
iii. the change in the gravitationalpotential energy of the object- Earth system when the object movesfrom the release point to it’s maximum height = 72.03J

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.