Question
A ball is thrown from the edge of a cliff with an initial velocity of 60·m/s upward. Answer the following questions using + (upward) and - (downward) to indicate the direction of the velocity. Ignore air resistance and assume the ball does not hit the ground during the question.
(a) Find the velocity of the ball 5 seconds after it is thrown. 1 m/s.
(b) Find the velocity of the ball 10 seconds after it is thrown. 2 m/s.
(c) How high does it rise above the edge of the cliff (from where it was thrown)? 3 m.
(a) Find the velocity of the ball 5 seconds after it is thrown. 1 m/s.
(b) Find the velocity of the ball 10 seconds after it is thrown. 2 m/s.
(c) How high does it rise above the edge of the cliff (from where it was thrown)? 3 m.
Answers
call g = -10m/s^2
v = vi - g t = +60 - 10t
when t = 5
v = 60 -10(5) = 10 m/s
when t = 10
v = 60 - 10 (10) = -40 m/s
y = yi + vi t - (1/2)g t^2
what is t at the top where v = 0 ??
0 = 60 - 10 t
t = 6 seconds to top
y = 0 + 60(6) -5 (36)
= 180
v = vi - g t = +60 - 10t
when t = 5
v = 60 -10(5) = 10 m/s
when t = 10
v = 60 - 10 (10) = -40 m/s
y = yi + vi t - (1/2)g t^2
what is t at the top where v = 0 ??
0 = 60 - 10 t
t = 6 seconds to top
y = 0 + 60(6) -5 (36)
= 180
Related Questions
A ball thrown from the edge of a 35m high cliff takes 3.5s to reach the ground below. What was the b...
a ball is thrown upward with an initial velocity of 38.9 m/s from the edge of a cliff of height H. T...
A ball is thrown vertically upward from the edge of a cliff of height 131 m. The initial velocity is...
A ball dropped without initial velocity at the edge of a cliff with a height of 24m. from the base o...