Answer:
A. Their same forces repel each other, and their opposite forces attract each other.
Explanation:
As we know by the property of electric charge that similar charges repel each other and opposite charges attracts each other
So here we have similar situation in magnets also
Two similar poles or like poles of magnet i.e. North - North poles or South - South poles always repel each other
And also we can see that opposite poles of magnet each other i.e. North pole and south pole always attract each other.
SO here correct answer is
A. Their same forces repel each other, and their opposite forces attract each other.
An equal and opposite force acting upwards
Answer:
The thickness of the foil is 0.017 mm.
Explanation:
Given that,
Weight = 7.5 oz = 212.6175 gm
Density = 2.70 g/cm³
Area of aluminium = 50 ft² = 46451.52 cm²
We need to calculate the thickness of the foil
Using formula of density
Where, A = area
t = thickness
m = mass
Put the value into the formula
Hence, The thickness of the foil is 0.017 mm.
Answer:
K = .3941 × 10³ W/m.K
Explanation:
Qcond = K A ΔT÷ L
∴K = Qcond ×L ÷ A ΔT
J ÷ S = P
P = I × V =Qcond
∴Qcond = I × V
= 0.6 A × 110 V
=66 W
L = 0.12 m
ΔT = 8 °C
Qcond =33 V
Area = (πD²) ÷ 4
= [π (4 × 10⁻² )²] ÷ 4
= 1.256 × 10⁻³ m²
∴A = 1.256 × 10 ⁻³³ m²
So K = ( Qcond × L ) ÷ A ΔT
= (33) (0.12 ) ÷ (1.256 ×10⁻³ ) × 8
= 0.3941 × 10³ W/m .K
