Which describes Einstein’s second postulate about the special theory of relativity? The speed of light in a vacuum is constant, and nothing is faster than the speed of light. The speed of light in a vacuum is constant, and some things are faster than the speed of light. The speed of light in a vacuum fluctuates, but nothing is faster than the speed of light. The speed of light in a vacuum fluctuates, and some things are faster than the speed of light.

The two most prominent wavelengths in the light emitted by a hydrogen discharge lamp are 656 nm(red) and 486 nm (blue). light from a hydrogen lamp illuminates a diffraction grating with 520lines/mm , and the light is observed on a screen 1.5m behind the grating. part a what is the distance between the first-order red and blue fringes? express your answer to two significant figures and include the appropriate units.

You throw a baseball directly upward at time =0 at an initial speed of 14.9 m/s. what is the maximum height the ball reaches above where it leaves your hand? ignore air resistance and take =9.80 m/s2.

1. when conducting a test on what kind of music increases the growth of plants, all of the following would fail to meet to fair test standard except (1 point) using different kinds of plants. giving some plants more water than others. exposing the plants to different types of music. using nutrient-rich soil for one and lesser soil for others. 2. engineering uses scientific thinking to solve real-world problems. (1 point) true false 3. what does it mean to test a hypothesis? (1 point) pass a quiz on other scientists’ results analyze only the results from scientific sources not make assumptions about how an experiment will turn out see if the results of an experiment are what the scientist predicted