Two cars approach each other from opposite directions each with a velocity of 54 km/h. One of the cars emits a note of frequency 480 Hz. What will be the approximate frequency heard in the other car before they cross each other?

Red light strikes a metal surface and electrons are ejected. if violet light is now used with a 10% greater intensity, what will happen to the ejection rate (number of ejected electrons per second) and the maximum energy of the electrons? a) greater ejection rate; same maximum energyb) same ejection rate; greater maximum energyc) greater ejection rate; greater maximum energyd) same ejection rate; same maximum energye) none of the above answers are correct

According to the image below, which season is about to begin in the southern hemisphere? a. summer b. autumn c. winter d. spring

The gravitational force between pluto and charon is 3.61 × 1018 n. pluto has a mass of 1.3 × 1022 kg, which is only slightly greater than charon’s mass of 1.6 × 1021 kg. how far apart are pluto and charon? 2.0 × 107 m 2.4 × 1012 m 3.8 × 1014 m 5.8 × 1024 m