Rutherford's nuclear model stated that a cloud of negative electrons surround the nucleus however scientists realized that electrons in a cloud around the nucleus of an atom would be attracted to the nucleus, causing the atom to collapse. Thus Bohr's model proposed that electrons were contained in shells and they orbit the nucleus at fixed distances.
Answer:
Explanation:
When the skier reaches the bottom of the slope , height lost by it
h = 50 sin32 m
= 26.5 m
potential energy lost
= mgh
Gain of kinetic energy
= 1/2 mv²
mgh = 1/2 mv²
v = √ 2gh
= √ (2x9.8 x 26.5)
= 22.8 m /s
b )
Let μ be the coefficient of kinetic friction required.
friction force acting
= μmg
work done by friction in displacement of d (40 m ) on horizontal surface
- μmg x d
This negative work will be equal to positive kinetic energy of the skier on horizontal surface .
= μmg x d = (1/2) m v²
μ = v² / (2 gd)
= 519.4 / (2 x 9.8 x 140 )
= .19
One of the essential concepts to solve this problem is the utilization of the equations of centripetal and gravitational force.
From them it will be possible to find the speed of the body with which the estimated time can be calculated through the kinematic equations of motion. At the same time for the calculation of this speed it is necessary to clarify that this will remain twice the ship, because as we know by relativity, when moving in the same magnitude but in the opposite direction, with respect to the ship the debris will be double speed.
By equilibrium the centrifugal force and the gravitational force are equal therefore
Where
m = mass spacecraft
v = velocity
G = Gravitational Universal Constant
M = Mass of earth
Radius of earth and orbit
Re-arrange to find the velocity
Replacing with our values we have
From the cinematic equations of motion we have to
Remember that the speed is double for the counter-direction of the trajectories.
Replacing
Therefore the time required is 3.778s
Answer:
Explanation:
Given that on the tree the gravitational energy stored is 8J
Then, mgh = 8J.
The apple begins to fall and hit the ground, what is the maximum kinetic energy?
Using conservation of energy, as the above is about to hit the ground, the apple is at is maximum speed, and the height then is 0m, so the potential energy at the ground is zero, so all the potential of the apple at the too of the tree is converted to kinetic energy as it is about to hits the ground. Along the way to the ground, both the Kinetic energy and potential energy is conserved, it is notice that at the top of the tree, the apple has only potential energy since velocity is zero at top, and at the bottom of the tree the apple has only kinetic energy since potential energy is zero(height=0)
So,
K.E(max) = 8J
Answer:
Diaphragm or Iris: Many microscopes have a rotating disk under the stage. This diaphragm has different sized holes and is used to vary the intensity and size of the cone of light that is projected upward into the slide.
Explanation:
