Reference no: EM1322220
True or False:
1. A scientific law can be changed if new evidence is found which contadicts it.
2. A turtle starting from rest achieves a speed of .10 m/s after 2 seconds. The acceleration of the turtle is .20 m/s squared.
3. If one bowling ball is dropped from a window and at the same time a second bowling ball is thrown horizontally from the same window, both bowling balls will strike the ground at the same time.
4. When you are in a car which make a right turn, you tend to feel yourself pushed towards the left side of the car. According to an obserber outside the car, you experience this sensation because centrifugal force pushes you away from the center of the curve.
5. A person in a windowless spaceship has no way of knowing whether the spaceship is at rest or is moving at a constant speed.
6. By cutting a piece of paper in half, you reduce the density of the paper by one half.
7. Accoding to Bernoulli's principle, the faster water flows through a pipe, the greater the pressure will be on the walls of the pipe.
8. Evaporation is a cooking process.
9. Light waves can be polarized because they are longitudinal waves.
10. Scientifically speaking, black and white are not colors. An object appears black when it absorbs all the visible colors of light, and it appears whhite when it reflects all the visible colors of light.
11. Light that strikes a piece of paper is reflected in many different directions. This proves that in some materials the angle of reflection does not necessarily equal the angle of incidence.
12. Tweetie hears meowing coming from behind the sofa, but cant see the cat. This is because sound waves are longer and bend around the sofa, while light waves are shorter, and bend much less.
13. Two electrically charged objects 1 meter apart each experience a repulsive force of 1 N. If the objects were two meters apart, they would each experience a repulsice force of 1/4 N.
14. After a balloon is rubbed against a wall, it may have a very high voltage. You can touch the balloon safely, though, because the charge on it is very small.
15. A transformer steps energy up or down.
16. All particles either electrons, bullets, or people- have a wavelength.
17. Material Z has a critical mass of 4 g. This means that a critical reaction will build up explosively in a 3 g sphere of the material, but not in a 5 g sphere.
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