Physics easy 10 points ?

2016-07-10 10:09 pm
A gray kangaroo can bound across a flat stretch of ground with each jump carrying it 10.0 m from the takeoff point.


1. If the kangaroo leaves the ground at a 22.0 ∘ angle, what is its takeoff speed ?



2. What is its horizontal speed ?

回答 (3)

2016-07-10 10:20 pm
✔ 最佳答案
vx = V cos22, vy = V sin22, 10m = vx t, t = 2vy/ g.
Hence,
10m = 2 vx vy /g = 2 V^2 cos(22) sin(22) / g =>
V^2 = (10 m)sin(44) * g = 68.08 m/s.
And that's the answer to #1.

Then, #2, vx = 68.08 m/s * cos(22 deg) = 63.12 m/s
2017-02-15 9:12 pm
10. You Can Get Out of a Black Hole
This is actually a joke; there is no way to get out of a black hole (that’s why they're black!) But the APS outreach website PhysicsCentral has an article about this fascinating subject.
Gray Arrow PhysicsCentral: Black Holes

9. Physics Teaches You to Think
Many people who have studied physics report it helps them develop critical thinking and problem-solving skills.
Gray Arrow American Institute of Physics: Skills Physics Bachelor's Use

8. Physics Explains
Learn why the sky is blue
Gray Arrow HyperPhysics: Blue Sky

Why the world goes round (you might have heard it was love, but Newton knew the real answer)
Gray Arrow HyperPhysics: Angular Momentum

Why global warming will have the Alaskans trading in their snow boots for flip-flops
Gray Arrow HyperPhysics: Greenhouse Effect
Gray Arrow APS Forum on Physics and Society: A Tutorial on the Basic Physics of Climate Change

7. Physics Helps with the MCAT and LSAT
Data from the American Institute of Physics show that physics majors get among the highest MCAT scores and the highest LSAT scores of all undergraduate majors.
Gray Arrow American Institute of Physics: MCAT, LSAT and Physics Bachelor's

6. Physics Gets You a Job
To learn more about those recession-proof jobs, check out these profiles of physicists working in a wide variety of careers:
Gray Arrow APS Careers: Physicist Profiles
Gray Arrow PhysicsCentral: People in Physics
Gray Arrow Physics Career Resource: Physicist Profiles

5. Physics Puts Your Math to Use
Mathematics provide the tools physicists use to understand the world we live in. Nobel Prize winner Eugene Wigner explored this theme in a famous essay:
Gray Arrow The Unreasonable Effectiveness of Mathematics in the Natural Sciences

4. Physicists Can Be Engineers
Almost a third of all physics bachelor's recipients who go into the private sector take engineering jobs. See more interesting physics employment facts:
Gray Arrow APS Careers in Physics

3. Physics is Versatile
Pictured are four physicists explore the near and far mysteries of the universe:

Keivan Stassun explores the mysteries of the universe.
Gray Arrow Profile of Keivan Stassun

Marta Dark-McNeese uses lasers to develop new medical techniques.
Gray Arrow Profile of Marta Dark-McNeese

Kate McAlpine became an international rap sensation with the Large Hadron Rap.
Gray Arrow Profile of Kate McAlpine
Gray Arrow Watch the Large Hadron Rap

Kenneth Jensen solves the world's energy problems for Makani Power.
Gray Arrow Profile of Kenneth Jensen

2. Physics Makes Things Possible
Without physics there would be no:

Grocery laser scanners
Space rockets
Light bulbs
Digital cameras
Cars
Cell phones
Airplanes
Solar panels
Fiber optics
DVD players
Computers
MP3 players
Flatscreen TVs
Getting the picture? To learn more about the physics behind these technologies, search for them at Discovery Communications' online resource, HowStuffWorks.
Gray Arrow HowStuffWorks Website

1. Physics Will Help You Get into College, Get a Job, and Find Love
Physics makes you more attractive to university recruiters, future employers, and that cutie you have your eye on. (You'll just have to trust us on that last one).
2016-07-10 10:40 pm
1. Use the range equation: x = V²sin(2Θ) / g
10.0 m = V² * sin44.0º / 9.8m/s²
V = 11.9 m/s

2. Vx = VcosΘ = 11.9m/s * cos22.0º = 11.0 m/s

Hope this helps!


收錄日期: 2021-04-21 19:16:11
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20160710140940AA1ytJz

檢視 Wayback Machine 備份