a body moves with an initial velocity of 30m/s and accelerates uniformly until it attains the velocity 8m/s. it then continues at that velocity for some time and accelerates uniformly to rest. the total time taken for the journey is the 40s and the total distance travelled is 2550 km. if the time spent accelerating is half that of travelling at constant velocity calculate velocity, calculate the acceleration

Given the following statements, which is the best

Asmall (but heavy) particle placed in a glass of water will follow a zigzag motion because the particle will bounce off of the water molecules it meets. this is called brownian motion. a physicist simulates this on a computer, by varying the distance a particle can travel (called the mean free length), on average, before it collides with a water molecule and assigning the change in motion to be one of 8 directions, each with a similar probability. by running the simulated particle (with the same mean free length) many times she determines that it should take 15 seconds, on average, for the particle to fall to the bottom, with a standard deviation of 1.5 seconds. next she lets a real particle fall through a glass of water and finds that it took 18 seconds. what does she conclude, and why?

What is the value of x in the this question ?