C.There is an invisible magnetic field around the magnet where it exerts magnetic force
Answer: false
Explanation: hope that helped
Answer:
56 J
Explanation:
The following data were obtained from the question:
Energy 1 (E₁) = 7 J
Extention 1 (e₁) = 1.8 cm
Extention 2 (e₂) = 1.8 + 3.6 = 5.4 cm
Energy 2 (E₂) =?
Energy stored in a spring is given by the following equation:
E = ke²
Where E is the energy.
K is the spring constant.
e is the extension.
E = ke²
Divide both side by e²
K = E/e²
Thus,
E₁/e₁² = E₂/e₂²
7/ 1.8² = E₂/ 5.4²
7 / 3.24 = E₂/ 29.16
Cross multiply
3.24 × E₂ = 7 × 29.16
3.24 × E₂ = 204.12
Divide both side by 3.24
E₂ = 204.12 / 3.24
E₂ = 63 J
Thus, the additional energy required can be obtained as follow:
Energy 1 (E₁) = 7 J
Energy 2 (E₂) = 63 J
Additional energy = 63 – 7
Additional energy = 56 J
Density d=m/V
mass m=d.V=13.5×5=67.5g
m=67.5g
hope this helps you
