[情報] 普物作業題目
15.A ball is tossed from an upper-story window of a building.
The ball is given an initial velocity of 8.00 m/s at an
angle of 20.0°below thehorizontal. It strikes the ground
3.00s later.(a)How far horizontally from the base of the
building does the ball strike the ground?(b) Find the
height from which the ball was thrown.(c)How long does it
take the ball to reach a point 10.0m below the level of
launching?
27.Figure P4.27 represents the total acceleration of a particle
moving clockwise in a circle of radius 2.50m at a certain
instant of time. At this instant, find(a)the radial acceleration,
(b)the speed of the particle, and(c)its tangential acceleration.
http://www.wretch.cc/album/show.php?i=j780719&b=4&f=1348217184&p=1
31.A river has a steady speed of 0.500m/s. A student swims upstream
a distance of 1.00km and swims back to the starting point. If the
student can swim at a speed of 1.20m/s in still water, how long
does the trip take? Compare this answer with the time interval
required for the trip if the water were still.
39.A pendulum with a cord of length r=1.00m swings in a vertical plane
(Fig.P4.39). When the pendulum is in the two horizontal positions θ
= 90.0°andθ270°,its speed is 5.00m/s
(a)Find the magnitude of the radial acceleration and tangential
acceleration for these positions.(b)Draw vector diagrams to determine
the direction of the total acceleration for these two positions.
(c)Calculate the magnitude and direction of the total acceleration.
http://www.wretch.cc/album/show.php?i=j780719&b=4&f=1348217185&p=2
46.A person standing at the top of a hemispherical rock of radius R kicks
a ball (initially at rest on the top of the rock)to give it horizontal
velocity Vi(向量上面有→)as shown in Figure P4.46.(a)What must be its
minimum initial speed if the ball is never to hit the rock after it is
kicked?(b)With this initial speed, how far from the base of the rock
does the ball hit the ground?
http://www.wretch.cc/album/show.php?i=j780719&b=4&f=1348217186&p=3
54.In the What If? section of Example 4.5, it was claimed that the maximum
range of a ski jumper occurs for a launch angle θgiven by θ=45°-φ/2
where φ is the angle that the hill makes with the horizontal in Figure
4.14. Prove this claim by deriving this equations.
密碼:mooix
--
※ 發信站: 批踢踢實業坊(ptt.cc)
◆ From: 218.164.226.60
推
10/11 10:46, , 1F
10/11 10:46, 1F
推
10/11 14:05, , 2F
10/11 14:05, 2F
推
10/11 17:18, , 3F
10/11 17:18, 3F
→
10/11 17:19, , 4F
10/11 17:19, 4F
→
10/11 17:47, , 5F
10/11 17:47, 5F
→
10/11 18:35, , 6F
10/11 18:35, 6F
→
10/11 18:38, , 7F
10/11 18:38, 7F
推
10/11 22:36, , 8F
10/11 22:36, 8F
→
10/11 23:01, , 9F
10/11 23:01, 9F
→
10/11 23:44, , 10F
10/11 23:44, 10F
討論串 (同標題文章)
完整討論串 (本文為第 1 之 2 篇):
情報
4
10