The density of the metal can be determined through the formula [n*MW]/ Na*[a^3] . substituting, we get,
<span>d = [n*MW]/ Na*[a^3]
</span><span>d = [4 atoms*42.3 g/mol]/ [6.022 x 1023atoms/mol* (sqrt 8 *1.20x10-10)^3]
</span>d = 0.719 g/cm3
Answer:
Explanation:
Sine the plane is horizontal , effect of gravity on horizontal motion will be nil.
Since no friction is acting on it , no horizontal force is acting on it. Since no vertical ,no horizontal force is acting on it , it will have uniform motion ,ie its velocity will remain unchanged during its motion , no matter how long the path is.
So , velocity along the path will remain unchanged.
Answer:
2.85 m
Explanation:
From trigonometry,
Cosine = Adjacent/Hypotenuse
Assuming, The wall, the ladder and the ladder forms a right angle triangle as shown in fig 1, in the diagram attached below.
cos∅ = a/H....................... Equation 1
Where ∅ = Angle the ladder makes with the horizontal, a = The horizontal distance from the bottom of the ladder to the wall, H = The length of the ladder.
make a the subject of the equation
a = cos∅(H)..................... Equation 1
Given: ∅ = 68 °, H = 7.6 m.
Substitute into equation 2
a = cos(68)×7.6
a = 0.375×7.6
a = 2.85 m.
Hence the horizontal distance from the bottom of the ladder to the wall = 2.85 m
Answer:
196J
Explanation:
Given parameters:
Mass of skateboard = 1kg
Height off the ground = 20m
Unknown:
Potential energy = ?
Solution:
The potential energy is the energy due to the position of a body above the ground.
It is mathematically expressed as:
Potential energy = mass x acceleration due gravity x height
Potential energy = 1 x 9.8 x 20 = 196J