Thanks for all your help you guys but I've already solved the
previous questions already. But here are some tougher ones. I do
not know how to solve the ones in bold...
A rock is thrown upward from the level ground in such a way that
the maximum height of its flight is equal to its horizontal range
d.
(a) At what angle θ is the rock thrown? 75.96°
(b) Would your answer to part (a) be different on a different
planet? No.
(c) What is the range d(max) the rock can attain if it is
launched at the same speed but at the optimal angle for maximum
range
___________ d
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A landscape architect is planning an artificial waterfall in a city
park. Water flowing at 2.17 m/s will leave the end of a horizontal
channel at the top of a vertical wall 2.35 m high, and from there
the water falls into a pool.
(a) Will the space behind the waterfall be wide enough for a
pedestrian walkway? Yes.
(b) To sell her plan to the city council, the architect
wants to build a model to standard scale, one-seventeenth actual
size. How fast should the water flow in the channel in the model?
____________ m/s
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A fish swimming in a horizontal plane has velocity vi = (4.00 i
+ 1.00 j) m/s at a point in the ocean where the position relative
to a certain rock is ri = (10.0 i + 4.00 j) m. After the fish swims
with constant acceleration for 21.0 s, its velocity is v = (19.0 i
- 5.00 j) m/s.
(a) What are the components of the acceleration?
Ans: a = 0.714 m/s^2 for x-direction
a = -0.286 m/s^2
for y-direction
(b) What is the direction of the acceleration with respect to unit
vector i?
Ans: -21.82 deg (counterclockwise from the +x-axis is positive)
(c) If the fish maintains constant acceleration, where is it at
t = 31.0 s?
Ans: x = 477.08 m, y = -102.42 m
(d) In what direction is it moving?
Ans: ___________ deg (counterclockwise from the +x-axis is
positive)