Use of lubricant
Use of ball bearers
Use of streamlined body
Use of graphite
A. Angular momentum is always conserved would be the correct answer.
This is because like linear momentum (mvmv), angular momentum (r×mvr×mv) is a conserved quantity, where rr is the vector from the center of rotation. For a skater holding a static pose, for each particle making up her body, the contribution in magnitude to the total angular momentum is given by mirivimirivi. Thus bringing in her arms reduces riri for those particles. In order to conserve angular momentum, there is then an increase in the angular velocity.
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Answer:
Speed of the airplane 10.0 s later = 12.2 m/s
Explanation:
Mass of Boeing 777 aircraft = 300,000 kg
Braking force = 445,000 N
Deceleration

Initial velocity, u = 27 m/s
Time , t = 10 s
We have equation of motion, v =u +at
v = 27 + (-1.48) x 10 = 27 - 14.8 = 12.2 m/s
Speed of the airplane 10.0 s later = 12.2 m/s
Answer:
The slope of a velocity graph represents the acceleration of the object. So, the value of the slope at a particular time represents the acceleration of the object at that instant.