Semi-trailer trucks have an odometer on one hub of a trailer wheel. the hub is weighted so that it does not rotate, but it contains gears to count the number of wheel revolutions—it then calculates the distance traveled. if the wheel has a 1.19 m diameter and goes through 120,000 rotations, how many kilometers should the odometer read?

If the speed of a particle triples ,by what factor does its kinetic energy increase?

Aparticle's position is given by x = 3.00 - 9.00t + 3t2, in which x is in meters and t is in seconds. (a) what is its velocity at t = 1 s? (b) is it moving in the positive or negative direction of x just then? (c) what is its speed just then? (d) is the speed increasing or decreasing just then? (try answering the next two questions without further calculation.) (e) is there ever an instant when the velocity is zero? if so, give the time t; if not, answer "0". (f) is there a time after t = 3 s when the particle is moving in the negative direction of x? if so, give the time t; if not, answer "0".

Why does a collision with an airbag cause less damage than a collision with a steering wheel