An object 10 cm high is placed in front of a convex mirror of focal length 20 cm and the object is 30 cm from the mirror. Find the height of the image.(Ans:12cm)​

An isotope undergoes radioactive decay by emitting radiation that has a –1 charge. what other characteristic does the radiation have?

Agraduated cylinder contains 63.0 ml of water. a piece of gold, which has a density of 19.3 g/ cm3, is added to the water and the volume goes up to 64.5 ml. calculate the mass in grams of the gold that was added to the water. explain how you got your answer.

Which statement is true if the refractive index of medium a is greater than that of medium b? a. total internal reflection is possible when light travels from air to medium b to medium a. b. total internal reflection is possible when light travels from medium a to medium b. c. total internal reflection is possible when light travels from medium b to medium a. d. total internal reflection is possible when light travels from air to medium a. e. total internal reflection is possible when light travels from air to medium b.