An object is placed 15 cm in front of a concave mirror with a focal length of 30 cm. What is the magnification?
a. 1
b. 2
c. 1/2
d. 1/4
e. ?2
b
You might also like to view...
What is a Cepheid variable?
A) It is a type of luminous star that makes an excellent standard candle. B) It is a bright source of variable x-ray emission, thought to harbor a supermassive black hole. C) It is a main-sequence star of spectral type B5. D) It is a type of galaxy that varies in its light output.
A star system can become a Type I supernova several times
Indicate whether the statement is true or false
14C has an activity of 0.25 Bq per gram of carbon for living organisms. The half-life of 14C is 5730 years. If a sample of charcoal from an archeological dig yields a 14C activity of 0.15 Bq per gram of carbon, how old is the material?
a. 
b. 
c. 
d. 
e. 
What does an electroscope do?
a. Measures the amount and sign of the charge of a given object. b. Takes on the opposite charge to an object brought in contact with it. c. Detects if an object is charged. d. Charges nearby objects. e. Responds only to negatively charged objects.