I believe it’s stay in motion if it’s not acted on by an unbalanced force
Force = mass x acceleration
15 = mass x 4
Mass = 15/4
Mass = 3.75 Kg
A human hair is approximately 50 μm = 5 × 10⁻⁵ m in diameter
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
Gravitational potential energy can be calculated using the formula <span>PE = m × g × h, where g is the gravitational acceleration and is constant hence the energy is dependent directly to mass and the height of the object. Hence more PE is registered when the object is heavier and/or at greater initial height. </span>
