What is required for a rocket to lift off into space?
a. thrust that is greater than earth’s gravity
b. mass that is greater than earth’s
c. very little air resistance
d. more velocity than friction

The speed of light in a material is 0.50 c. what is the critical angle of a light ray at the interface between the material and a vacuum?

The force acting on a beam was measured under the same operating conditions and a sample of 5 data points was collected. this process was repeated by 3 observers. the pooled standard deviations of these 3 data sets was 1.21. determine the true mean force using all pooled data (with a 95% probability). the result should look like this: true mean = mean +/- margin of error

What is the thinnest soap film (excluding the case of zero thickness) that appears black when illuminated with light with a wavelength of 480 ? the index of refraction of the film is 1.34, and there is air on both sides of the film. express your answer in nanometers. hint 1. how to approach th