Single movable pulley has 2 VR because in single fixed pulley, load is supported with two segments of the string. It makes the effort distance double of the load distance. {As VR = No.of pulley used or number of rope segments that supports the load.}
We can calculate the amount of heat transfer by means of the following expression that includes the mass and temperature change in a body as a function of the specific heat.
1) d = V*t >>>as you double the av. speed the distance become doubled. 2) after you draw the victors you will find the total displacement = 1 meter to the left. 3) V =d/t =( 8km)/(1.25hr) = 6.4km/hr
