Density is mass over volume:
In your case, mass is 48 grams and volume is 12cm^3
If you put that into the equation, you will get your density:
<u>Answer
</u>
D. Salt water is denser than freshwater.
<u>Explanation</u>
A boat is able to float on water because it experiences an upthrust upwards.
The magnitude of the upthrust depends on the density of the liquid.
When the liquid is denser the boat will experience a great upthrust as compared to when in a less dense liquid.
If the boat sinks lower in the freshwater than in salty water, then Salt water is more dense than freshwater.
Answer:
the internal resistance of the cell is 0.1 ohm.
Explanation:
Given;
p.d at the terminals of a battery at no load, E₁ = 25 V
p.d at the terminals of a battery at a load, E₂ = 24 V
current through the circuit, I = 10 A
The potential drop across the circuit, V = E₁ - E₂
= 25 V - 24 V
= 1 V
The internal resistance of the cell is calculated as follows;
r = V/I
r = 1 / 10
r = 0.1 ohm
Therefore, the internal resistance of the cell is 0.1 ohm.
One of the efficient concepts that can help us find the number of turns of the cable is through the concept of induced voltage or electromotive force given by Faraday's law. The electromotive force or emf can be described as,
Where,
N = Number of loops
B = Magnetic Field
A = Cross-sectional Area
= Angular velocity
Re-arrange to find N,
Our values are given as,
Replacing at our equation we have:
Therefore the number of loops of wire should be wound on the square armature is 32 loops
Answer:
c) 2.02 x 10^16 nuclei
Explanation:
The isotope decay of an atom follows the equation:
ln[A] = -kt + ln[A]₀
<em>Where [A] is the amount of the isotope after time t, k is decay constant, [A]₀ is the initial amount of the isotope</em>
[A] = Our incognite
k is constant decay:
k = ln 2 / Half-life
k = ln 2 / 4.96 x 10^3 s
k = 1.40x10⁻⁴s⁻¹
t is time = 1.98 x 10^4 s
[A]₀ = 3.21 x 10^17 nuclei
ln[A] = -1.40x10⁻⁴s⁻¹*1.98 x 10^4 s + ln[3.21 x 10^17 nuclei]
ln[A] = 37.538
[A] = 2.01x10¹⁶ nuclei remain ≈
<h3>c) 2.02 x 10^16 nuclei</h3>
