A boy runs in a 125-m race from rest. In the first 5 seconds, he increases his speed with a constant acceleration of 2.0 m/s2. He then maintains this speed for the rest of the run. Calculate the total
time taken for the boy to finish the run.

Total solidification times of three casting geometries are to be compared: a sphere, a cylinder, in which the length-to-diameter ration - 1.0, and a cube. volume = 1000 cm^3 for all three shhapes, and the same casting alloy is used. a) determine the solidification times of each geometry b) based on the results of part (a), which geometric element would make the best riser? c) if the mold constant = 3.5 min/cm^2 in chvorinov's rule, compute the total solidification time for each casting.

Two polarizers are oriented at 40∘ to each other and plane-polarized light is incident on them. if only 16 percent of the light gets through both of them, what was the initial polarization direction of the incident light?

What object a collides with object b and bounces back its final momentum is?