Answer:
15.C Mucus reduces friction
C is the breakdown of rock and soil on earths surface. Think of the grand canyon.
Answer:
a)W= - 47.19 J
b)47.19 J
Explanation:
Given that
Weight ,mg= 71.5 N
y= 1.84 m
H= 2.5
a)
The distance above the hand ,h= 2.5 - 1.84 m
h= 0.66 m
We know that gravitaional force act in the downward direction but the displacement is in upward direction that is why work done will be negative.
W= - m g h
W= -71.5 x 0.66 J
W= - 47.19 J
b)
The potential energy at initial position = m g y
The potential energy at final position = m g H
So change in the potential energy = m g H - m g y
= mg ( H- y)
=71.5 ( 2.5 - 1.84 ) = 47.19 J
Therefore change in the potential energy = 47.19 J
Answer:
Hey there!
They used math to explain their observations, for example, Newton is famous for his three laws, and universal laws of gravitation.
Let me know if this helps :)
