realtive velocity

A Physics teacher explains the concept of relative velocity to her students in class. She emphasises that when two bodies are moving in opposite directions, their relative velocity is sum of the velocities of the two. And when two bodies are moving in the same direction, their relative velocity is difference of the velocities of the two. Students are confused. The teacher then takes two balls one red and the other green. She says suppose red ball moves with a velocity 5 m//s and green ball moves with a velocity of 4 m//s from a common point, and along the same straight line. if red ball is moving to the right and green ball is moving to the left, then after 1 sec , red ball is at R' , where R R' = 5 m and green ball is at G' where G G' = 4 m , Figure. The distance between the two balls after 1 sec = G' R' G G' + R R' = (4 + 5) = 9 m . This is the magnitude of their realtive velocity. If both the balls are moving to the right, as shown in Figure. The distance between the two balls after sec = G' R' - G G' = 5 - 4 = 1 m . In that case, relative velocity = 1m//s . (a) Read the above passage and answer the following questions : (i) What value has the Physics teacher displayed ? (ii) What have the students picked up ? (iii) Give atleast one practical example of the concept.

Two particles are moving with velocities v_(1) and v_2 . Their relative velocity is the maximum, when the angle between their velocities is

Define relative velocity. Deduce an expression for relative velocity of one object with respect to another in terms of their velocities relative to the earth.

The realtive density of mercury is 13.6. Find the ratio of the mass of mercury of a certain volume to that of water having ten times the volume of mercury.

A stream line body with relative density rho_(1) falls into air from a height h_(1) on the surface of a liquid of realtive density rho_(2) , where rho_(2) gt rho_(1) . Find the time of immersion of the body into the liquid.

two bodies counterpoise each other when suspended in water from the arms of a balance. The mass of one body is 0.28 kg and its relative density 5.6 . It the mass of the other is 0.36 kg, what is the realtive density of the other body ?

Most probable velocity, average velocity and root mean square velocity are related as

The relation between wave velocity and maximum particle velocity is (Where V_(p) = Particle velocity, V = Wave velocity)

Wave velocity & particle velocity from wave equation