Answer:


Explanation:
r = Radius = 2.7 cm
F = Force = 
A = Area = 
= Stress = 
E = Young's modulus = 
= Strain
= Original length = 67 cm
= Change in length
Young's modulus is given by

Strain is 
Strain is given by

The cylinder height decreases by 
Answer:
The time it takes the ball to fall 3.8 meters to friend below is approximately 0.88 seconds
Explanation:
The height from which the student tosses the ball to a friend, h = 3.8 meters above the friend
The direction in which the student tosses the ball = The horizontal direction
Given that the ball is tossed in the horizontal direction, and not the vertical direction, the initial vertical component of the velocity of the ball = 0
The equation of the vertical motion of the ball can therefore, be represented by the free fall equation as follows;
h = 1/2 × g × t²
Where;
g = The acceleration due gravity of the ball = 9.81 m/s²
t = The time of motion to cover height, h
Then height is already given as h = 3.8 m
Substituting gives;
3.8 = 1/2 × 9.81 × t²
t² = 3.8/(1/2 × 9.81) ≈ 0.775 s²
∴ t = √0.775 ≈ 0.88 seconds
The time it takes the ball to fall 3.8 meters to friend below is t ≈ 0.88 seconds.
Answer:
person when the point-light walker is moving
Explanation:
A point light walker is an arrangement of dots that moves in a way that mimics a human walking. This is used in the field of Biological Motion Perception.
Biological motion perception is the science that deals with how our brain perceives motion. In order to understand how the brain perceives motion a point light walker is used.
Gravitational acceleration is approx 9.8 m/s
Time is 7s
a=9.8 m/s
t=7s
a = d/t^2
therefore:
d = a * t^2
d = 9.8 * 7^2
d = 9.8 * 49
d = 480.2 [m]