Aconstant driving force is applied to the car for the first 6 sec. at time t=16 sec the driver realises the car is travelling too fast for the 22 m s-1 speed limit (50 miles per hour and applies the break until time t=18 s.

a. calculate the acceleration at time t=3sec

Part a constants huck finn walks at a speed of 0.60 m/s across his raft (that is, he walks perpendicular to the raft's motion what is huck's velocity (speed and direction) relative to the river bank? express your answer to three significant figures and include the appropriate units. relative to the shore)

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.

What does si stand for,when referring to a system of measurement