1. A stopwatch starts while race car travels at 7 m/s from the pit area and accelerates at a uniform rate to a speed of 30 m/s in 19 s moving on a circular track of radius 511 m. Assuming constant tangential acceleration, find
(a) the tangential acceleration, and
(b) the radial acceleration, at the instant when the speed is v = 15
Once you have both of those ... find the magnitude of a at any moment

2. A stopwatch starts while race car travels at 12.0 m/s from the pit area and accelerates at a uniform rate to a speed of 33 m/s in 16 s moving on a circular track of radius 502 m.
Assuming constant tangential acceleration, find
(a) the tangential acceleration, and
(b) the radial acceleration, at the instant when the speed is v = 17
Once you have both of those ... find the magnitude of a at any moment

3. A stopwatch starts while race car travels at 6 m/s from the pit area and accelerates at a uniform rate to a speed of 25 m/s in 3 s moving on a circular track of radius 492 m.
Assuming constant tangential acceleration, find
(a) the tangential acceleration, and
(b) the radial acceleration, at the instant when the speed is v = 6
Once you have both of those ... find the magnitude of a at any moment

uranium fissions/breaks up giving out energy and neutrons

russian is not my first language, so i'm afraid i can't write out an answer in russian, but hopefully you can find a way to do so. here's my best translation of the problem: you're given a plot of a particle's position in one-dimensional space over time, and you're asked to find either the total distance traveled by the particle after 6 seconds had elapsed, or the total displacement of the particle after 6 seconds.

if you want the total distance traveled, you would first need to determine the particle's velocity as a function of time, then integrate that over the 6-second interval. we know the position function is quadratic with roots at 0 and 6, so we have

where is unknown. because the position is parabolic, there is symmetry about the midpoint at , and we know that

so that the position function is

which means the velocity is

then the total distance traveled is

so the total distance traveled is 20 m.

on the other hand, if you want to find displacement: the particle starts at and ends at , so its displacement is 0.

b. a lightning bug, plug of grass, and a worm

according to jean piaget, in what stage of cognitive development are children able to understand conservation task?

b. preoperational

just took it