Water in the Earth system is influencing all aspects of life on Earth. ... The returning water falls directly back into the oceans, or onto land as snow or rain. It soaks into the soil to move into the groundwater or runs off the Earth's surface in streams, rivers and lakes, which drain back into the oceans.
9.8 is the gravitational field strength on earth, perhaps re-read the question
We know that the centripetal acceleration is zero, since the summation of forces is the mass times the acceleration in the x- component.
Answer:
Explanation:
It is given that,
Angular speed of the football spiral, 
Radius of a pro football, r = 8.5 cm = 0.085 m
The velocity is given by :
v = 3.68 m/s
The centripetal acceleration is given by :
So, the centripetal acceleration of the laces on the football is 
. Hence, this is the required solution.
Answer:
<em>0.25</em>
Explanation:
According to newtons law of motion
\sum F_x = ma
F_f = ma
nR = ma
nmg = ma
ng = a
n = a/g
g is the acceleration due to gravity
Given
a = 2.42m/s²
g = 9.8m/s²
Substitute into the formula;
n = 2.42/9.8
n = 0.25
<em>Hence the coefficient of kinetic friction is 0.25</em>
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