Answer:
) the uniform disk has a lower moment of inertia and arrives first.
Explanation:
(a) the uniform disk has a lower moment of inertia and arrives first.
(b) Let's say the disk has mass m and radius r, and
the hoop has mass M and radius R.
disk: initial E = PE = mgh
I = ½mr², so KE = ½mv² + ½Iω² = ½mv² + ½(½mr²)(v/r)² = (3/4)mv² = mgh
m cancels, leaving v² = 4gh / 3
hoop: initial E = Mgh
I = MR², so KE = ½MV² + ½(MR²)(V/R)² = MV² = Mgh
M cancels, leaving V² = gh
Vdisk = √(4gh/3) > Vhoop = √(gh)
Answer:
105000km
Explanation:
Given parameters:
Speed of shuttle = 21000km/hr
Time of travel = 5hrs
Unknown:
The distance covered by the space shuttle;
Solution:
Distance is the length of the path traveled.
Distance = speed x time
Input the parameters and solve;
Distance = 21000km/hr x 5hrs
Distance = 105000km
Answer:
Explanation:
Lead has an half life of 43.5 seconds
The radioactive decay law says
N(t) = No•2^(-t / t½)
Hence, the percent of a sample of the Lead-214 isotope that decay after a time equivalent to 7 half-lives
N(t) = No•2^(-t / t½)
N(t) / No = 2^(-t / t½)
N(t) / No = 2^-7
N(t) / No = 7.81 × 10^-3
To percentage
N(t) / No = 7.81 × 10^-3 × 100
N(t) / No = 0.781 %
Oceanography is the branch of science that deals with the physical and biological properties and phenomena of the sea.