Answer: The density of this piece of jewelry is 
Explanation:
To calculate the density, we use the equation:
Mass of piece of jewellery = 130.8 g
Density of piece of jewellery = ?
Volume of piece of jewellery =( 62.4-47.7 ) ml = 14.7 ml = 
Putting values in above equation, we get:
Thus density of this piece of jewelry is
Answer:
The kinetic energy K of the moving charge is K = 2kQ²/3d = 2Q²/(4πε)3d = Q²/6πεd
Explanation:
The potential energy due to two charges q₁ and q₂ at a distance d from each other is given by U = kq₁q₂/r.
Now, for the two charges q₁ = q₂ = Q separated by a distance d, the initial potential energy is U₁ = kQ²/d. The initial kinetic energy of the system K₁ = 0 since there is no motion of the charges initially. When the moving charge is at a distance of r = 3d, the potential energy of the system is U₂ = kQ²/3d and the kinetic energy is K₂.
From the law of conservation of energy, U₁ + K₁ = U₂ + K₂
So, kQ²/d + 0 = kQ²/3d + K
K₂ = kQ²/d - kQ²/3d = 2kQ²/3d
So, the kinetic energy K₂ of the moving charge is K₂ = 2kQ²/3d = 2Q²/(4πε)3d = Q²/6πεd
Explanation:
The weight of the car is equal to, 
...........(1)
Where
m is the mass of car
g is the acceleration due to gravity
The normal or vertical component of the force is, 
or
.............(2)
The horizontal component of the force is, 
Taking ratio of equation (1) and (2) as :
or
Hence, this is the required solution.
Answer:
ω = 1.83 rad/s clockwise
Explanation:
We are given:
I1 = 3.0kg.m2
ω1 = -5.4rad/s (clockwise being negative)
I2 = 1.3kg.m2
ω2 = 6.4rad/s (counterclockwise being positive)
By conservation of the momentum:
I1 * ω1 + I2 * ω2 = (I1 + I2) * ω
Solving for ω:
Since it is negative, the direction is clockwise.
During a total lunar eclipse, the Moon located in the umbra.
The answer is letter A. For a total lunar eclipse to occur, the Sun, Earth and
Moon must be aligned in a straight line. The Earth’s umbra complete covers the
Moon. The earth’s umbra is about 870,000 miles wide.
