When do the sun’s rays strike latitude 23.5°S at an angle of 90 degrees?

September 21

December 21

March 21

June 21

The earth remains in orbit around the sun due to the force of gravity. how does the force of gravity exerted by the sun on the earth compare to the force of gravity exerted by the earth on the sun?

The focal length of a relaxed human eye is approximately 1.7 cm. when we focus our eyes on a close up object, we can change the refractive power of the eye by about 16 diopters. (a) does the refractive power of our eyes increase or decrease by 16 diopters when we focus closely? explain. (b) calculate the focal length of the eye when we focus closely.

Achild has maximum walking speed of 1.6 m/s. what is the length of the child's legs? 0.26 m