Answer:
a) αA = 4.35 rad/s²
αB = 1.84 rad/s²
b) t = 3.7 rad/s²
Explanation:
Given:
wA₀ = 240 rpm = 8π rad/s
wA₁ = 8π -αA*t₁
The angle in B is:



The velocity at the contact point is equal to:


Matching both expressions:

b) The time during which the disks slip is:

a) The angular acceleration of each disk is


Answer:
False
Explanation:
An object in uniform circular motion must be changing its velocity in order to move in a circular path.
In fact, remind that velocity is a vector which consists of a magnitude (the speed) and a direction.
When an object is moving in uniform circular motion, the direction of the motion is constantly changing (since the trajectory is a circle): so, this means that the velocity is also changing. However, this does not imply that the speed of the object is changing. In fact, in a uniform circular motion, the speed of the object remains constant.
E concave mirror because it reflects the light
Answer:
D. Wind turbines take up a lot of space.
Explanation:
In wind turbines the kinetic energy received by the air molecules is converted into electrical energy by the use of turbines
So here in order to get more kinetic energy from air we need more crossectional area of the wind mill to interact with the air
So here we need the large size of turbines
so this is the main disadvantage of the wind turbines because it needs large area to install the whole setup also the efficiency of this turbine is small so it needs large number of wind mills to setup good output power
so correct answer will be
D. Wind turbines take up a lot of space.