Static electricity is the result of an imbalance between negative and positive charges in an object. These charges can build up on the surface of an object until they find a way to be released or discharged. ... The rubbing of certain materials against one another can transfer negative charges, or electrons.
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
Error is the difference between the true value of the measurand and the measured value.. Uncertainty characterizes the range of values within which the true value is asserted to lie with some level of confidence.
If that doesn’t help here’s the definition of both the terms,
Error:
A mistake
Uncertainty:
the state of being uncertain.
Explanation:
a. " for every action there is an equal and opposite reaction".
b. The electric fan does not stop moving just after the switch turns off because of rational inertia force.
c. The force applied to first vehicle is 120N.
d. In my view it doesn't support the law of conservation of momentum. Momentum of 1 and 2 object before the collision is equal to the total momentum of two object after collision.
Answer:
There are 8345714 cell membranes.
Explanation:
It is given that,
The thickness of a cell membrane is 7 nm
We need to find the number of cell membranes would it take to make a stack 2.3 inches high.
Firstly, the units must be same i.e. converting 2.3 inches to m
1 inch = 0.0254 m
2.3 inches = 0.05842 m
Let there are n number of cell membranes. So,
or
n = 8345714 cell membranes
