Its to blury for me to see it
Answer:

Explanation:
let A represent me and B represent my friend
A speed
=30 m/hr toward west
B speed
=40 m/hr toward south
after 1/2 hr
total distance cover by A =1/2 * 30 miles = 15 miles
total distance by B = 1/2*40 miles = 20 miles
now from figure


Differentiate above equation




We know that tangential acceleration is related with radius and angular acceleration according the following equation:
at = r * aa
where at is tangential acceleration (in m/s2), r is radius (in m) aa is angular acceleration (in rad/s2)
So the radius is r = d/2 = 1.2/2 = 0.6 m
Then at = 0.6 * 5 = 3 m/s2
Tangential acceleration of a point on the flywheel rim is 3 m/s2
Answer:
The time it can operate between chargins in minutes is

Explanation:
Given:
,
, 
a). The rotational kinetic energy






b). The power average 0.8kW un range time can be find

Solve to t'



When the heat source is removed from a fluid, convection currents in the fluid will eventually distribute heat uniformly throughout the fluid. When all of the fluid is at the same temperature, convection currents will stop.