Hai địa điểm a và b cách nhau 72km. cùng lúc, một ô tô đi từ a và một người đi xe đạp từ b ngược chiều nhau và gặp nhau sau 1h12 phút. sau đó ô tô tiếp tục về b rồi quay lại với vân tốc cũ và gặp lại người đi xe đạp sau 48 phút từ lần gặp trước. a/ tính vân tốc của ô tô và xe đạp?
b/ nếu ô tô tiếp tục đi về a rồi quay lại thì sẽ gặp người đi xe đạp sau bao lâu( kể từ lần gặp thứ 2)

Unpolarized light of intensity i_0=750w/m^2 is incident upon two polarizers. after passing through both polarizers the intensity is i_2=280w/m^2. (a) what is the intensity of the light after it passes through the first polarizer in w/m^2? (b) write an equation for the angle between the polarizers in terms of the initial (i_0) and final (i_2) intensities. (c) find the angle between the polarizers in degrees.

When temperature of a substance increases, of its particles increase resulting in more between particles. real world applications of thermal expansion absolute zero (-273 degrees c) is the lowest possible temperature on the kelvin scale. it is a measure of where a substance has no kinetic energy. heat is a process of the . energy flows spontaneously from a object to a until equilibrium is reached. heat is measured in heat is transferred throughis a method of heat transfer that occurs between particles of matter that are in direct contact with each other. are poor conductors that impede / reduce the rate of heat transfer. is a method of heat transfer that occurs in fluids (non-solids) by means of currents. real world application of convectiona method of heat transfer through electromagnetic waves. when energy moves from one object to another inside a closed system, no energy is or in the system in the transaction. systems will spontaneously move to a state of organized energy or high disorder over time called

Steelhead trout migrate up stream to spawn. occasionally they need to leap up small waterfalls to continue their journey. fortunately, steelhead are remarkable jumpers, capable of leaving the water at a speed of 8.0 m/s. a. what is the maximum height a steelhead trout can jump? b. leaving the water at 8.0 m/s, the trout lands on top of the water fall 1.8 m high. how long was it in the air?