When the cyclist encounters a steep hill, in order to maintain the same energy consumption and pedaling rate she changes her gear ratio to 0.7. Which of the following statements describes the change caused by the new gear ratio?

(a) The angular speed of the rear gear increases.
(b) The torque exerted on the rear gear wheel increases.
(c) The torque exerted on the front gear wheel increases.
(d) The power delivered to the rear gear wheel increases.

One day, after pulling down your window shade, you notice that sunlight is passing through a pinhole in the shade and making a small patch of light on the far wall. you see that the patch of light seems to be a circular diffraction pattern. it appears that the central maximum is about 1 cm across and you estimate that the distance from the window shade to the wall is about 3 m. what is (a) the average wavelength of sunlight? (b) the diameter of the pinhole?

True or false: the revolution of the earth creates day and night as it rotates around the sun

Waves that cause the most damage during an earthquake are a. surface waves c. s waves b. p waves d. ocean waves