Explain what causes the quarter to be attracted to the magnet ONLY when the magnet is moving quickly near the quarter. TWO WORDS ONLY!

In a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina. what should be the radius of curvature of the cornea such that the image of an object 40.0 cm from the cornea’s vertex is focused on the retina?

If angle "a" is 25°, angle "b" is: a) equal to angle c b) less than angle c c) greater than angle c

Aboy with a mass 25 kg climbs into a small tree. he sits on a branch that is 2.o m above to the ground. what is his gravitational potential energy above the ground?