B. Transverse Wave this is the correct answer
This is where we have to admit that gravitational potential energy is
one of those things that depends on the "frame of reference", or
'relative to what?'.
Potential energy = (mass) x (gravity) x (<em>height</em>).
So you have to specify <em><u>height above what</u></em> .
-- With respect to the ground, the ball has zero potential energy.
(If you let go of it, it will gain zero kinetic energy as it falls to
the ground.)
-- With respect to the floor in your basement, the potential energy is
(3) x (9.8) x (3 meters) = 88.2 joules.
(If you let go of it, it will gain 88.2 joules of kinetic energy as it falls
to the floor of your basement.)
-- With respect to the top of that 10-meter hill over there, the potential
energy is
(3) x (9.8) x (-10) = -294 joules
(Its potential energy is negative. After you let go of it, you have to give it
294 joules of energy that it doesn't have now, in order to lift it to the top of
the hill <em>where it will have zero</em> potential energy.)
Answer:
Net force: 20 N to the right
mass of the bag: 20.489 kg
acceleration: 0.976 m/s^2
Explanation:
Since the normal force and the weight are equal in magnitude but opposite in direction, they add up to zero in the vertical direction. In the horizontal direction, the 195 N tension to the right minus the 175 force of friction to the left render a net force towards the right of magnitude:
195 N - 175 N = 20 N
So net force on the bag is 20 N to the right.
The mass of the bag can be found using the value of the weight force: 201 N:
mass = Weight/g = 201 / 9.81 = 20.489 kg
and the acceleration of the bag can be found as the net force divided by the mass we just found:
acceleration = 20 N / 20.489 kg = 0.976 m/s^2
The average electric current in the lightning will be 8 ×
A
<h3>
Why Lightning Conductors on top of a tower ?</h3>
The lightning conductors are long metal strips running from the spike end of a conductor on the top of a building to the earth. They are used to prevent buildings from destruction when struck by thunder or lightning.
Given that a lightning strike can transfer as much as electrons from the cloud to the ground. if the strike lasts 2ms, to calculate the average electric current in the lightning, we will first consider the charge released.
one charge = 1.6 ×
C
Average current I = Q/t
Where
- Q = charge = 1.6 ×
C
- t = time = 2ms = 2 ×
s
Substitute all the parameters into the formula
I = 1.6 ×
C ÷ 2 × ![10^{-3}](https://tex.z-dn.net/?f=10%5E%7B-3%7D)
I = 8 ×
A
Therefore, the average electric current in the lightning will be 8 ×
A
Learn more about Lightning here: brainly.com/question/3183045
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D. dull and brittle when solid