The answer is A
Materials that are good conductors of thermal energy are called thermal conductors. Metals are very good thermal conductors. Materials that are poor conductors of thermal energy are called thermal insulators. Gases such as air and materials such as plastic and wood are thermal insulators
given,
mass of bicyclist(m)=90Kg
centripetal acceleration(a)=1.5 m/s2
centripetal force(F)=ma= 90×1.5=145 N
a) we can answer the first part of this by recognizing the player rises 0.76m, reaches the apex of motion, and then falls back to the ground we can ask how
long it takes to fall 0.13 m from rest: dist = 1/2 gt^2 or t=sqrt[2d/g] t=0.175
s this is the time to fall from the top; it would take the same time to travel
upward the final 0.13 m, so the total time spent in the upper 0.15 m is 2x0.175
= 0.35s
b) there are a couple of ways of finding thetime it takes to travel the bottom 0.13m first way: we can use d=1/2gt^2 twice
to solve this problem the time it takes to fall the final 0.13 m is: time it
takes to fall 0.76 m - time it takes to fall 0.63 m t = sqrt[2d/g] = 0.399 s to
fall 0.76 m, and this equation yields it takes 0.359 s to fall 0.63 m, so it
takes 0.04 s to fall the final 0.13 m. The total time spent in the lower 0.13 m
is then twice this, or 0.08s
A. Solid
Solid structures are actually made of repeating patterns.
Answer:
Angular acceleration, is 
Explanation:
Given that,
Initial speed of the drill, 
After 4.28 s of constant angular acceleration it turns at a rate of 28940 rev/min, final angular speed, 
We need to find the drill’s angular acceleration. It is given by the rate of change of angular velocity.
So, the drill's angular acceleration is .
