Two students are on a balcony 18.6m above the street. Onestudent throws a ball v

Question

Two students are on a balcony 18.6m above the street. Onestudent throws a ball vertically downward at 15.3 m/s. At the sameinstant, the other student throws a ball vertically upward at thesame speed. The second ball just misses the balcony on the waydown. (Hints: the ball that goes up and then down can bethought of doing two separate things: (1) traveling up and (2)traveling down. (Their explanation in the solutions is not great.)For the entire trip, the second ball returns to the same positionit started from) a) What is the magnitude of the velocity of the firstball as it strikes the ground? in units ofm/s. b) What is the magnitude of the velocity of the secondball as it strikes the ground? in units ofm/s. c) What is the difference in the time the balls spend inthe air? Answer in units of s. d) How far apart are the balls 0.571 s after they arethrown? Answer in units of m. a) What is the magnitude of the velocity of the firstball as it strikes the ground? in units ofm/s. b) What is the magnitude of the velocity of the secondball as it strikes the ground? in units ofm/s. b) What is the magnitude of the velocity of the secondball as it strikes the ground? in units ofm/s. c) What is the difference in the time the balls spend inthe air? Answer in units of s. d) How far apart are the balls 0.571 s after they arethrown? Answer in units of m. d) How far apart are the balls 0.571 s after they arethrown? Answer in units of m.

Explanation / Answer

a) What is the magnitude of the velocity of the first ball asit strikes the ground? in units of m/s.

v=15.32+2*9.8*18.6=234.09+364.56=24.46m/sec b) What is the magnitude of the velocity of the second ball asit strikes the ground? in units of m/s.=
since the second ball also gets the same speed when it reaches thesame point 0f projection it also gains the same velocity when itreaches ground.
so magnitude of velocity=24.46m/sec
b) What is the magnitude of the velocity of the second ball asit strikes the ground? in units of m/s.=
since the second ball also gets the same speed when it reaches thesame point 0f projection it also gains the same velocity when itreaches ground.
so magnitude of velocity=24.46m/sec
c) What is the difference in the time the balls spend in theair? Answer in units of s.
difference=time of flight of second ball to reach the firstpoint of projection.
hence time difference=2u/g=2*15.3/9.8=3.1224sec
d) How far apart are the balls 0.571 s after they are thrown?Answer in units of m.

during this time the first will be moving down wards and the secondball will be moving upwards.
height covered by the second ball in this time
h= 15.3*0.571-4.9*0.5712=8.7363-1.5976=7.1386m
in the same time distance covered by the first ball
h=15.3*0.571+4.9*0.5712=8.7363+1.5976=10.3339m
now the separation between these twoballs=7.1386+10.3339=17.4725m d) How far apart are the balls 0.571 s after they are thrown?Answer in units of m.

during this time the first will be moving down wards and the secondball will be moving upwards.
height covered by the second ball in this time
h= 15.3*0.571-4.9*0.5712=8.7363-1.5976=7.1386m
in the same time distance covered by the first ball
h=15.3*0.571+4.9*0.5712=8.7363+1.5976=10.3339m
now the separation between these twoballs=7.1386+10.3339=17.4725m

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

---

---

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