The box is in equilibrium, so Newton's second law says
<em>n</em> + (-<em>w</em>) = 0
65 N + (-<em>f</em> ) = 0
where <em>n</em> denotes the magnitude of the normal force, <em>w</em> denotes the weight of the box, and <em>f</em> denotes the magnitude of the friction force.
The box has a weight of
<em>w</em> = (25 kg) (9.80 m/s²) = 245 N
so <em>n</em> = 245 N, too.
The friction force has magnitude
<em>f</em> = 65 N
and is proportional to the normal force by a factor of <em>µ</em>, the coefficient of kinetic friction. So we have
65 N = <em>µ</em> (245 N) → <em>µ</em> ≈ 0.26
The coefficient is needed in front of NaNO3 to balance the equation is 2.
<h3>What is balanced equation?</h3>
When in a chemical reaction, both the product elements or compounds should have number of moles equal to that of the elements or compounds of reactants.
In the given chemical reaction equation,
Na2S + Zn(NO3)2 → ZnS + _NaNO3
Number of moles of S is 1 on both the product and reactant side. Zn has 1 mole on both side. NO3 has 2 mole and Na has 2 mole on reactant side. So to balance the equation, Na and NO3 both must have 2 moles on product side.
Thus, the coefficient is needed in front of NaNO3 to balance the equation is 2.
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time to reach an angular velocity of 36.8 is 24.370 s.
<h3>
</h3><h3>What is angular acceleration?</h3>
The temporal rate at which angular velocity changes is referred to as angular acceleration. Naturally, there are two forms of angular acceleration, referred to as spin angular acceleration and orbital angular acceleration, just as there are two types of angular velocity, namely spin angular velocity and orbital angular velocity. As opposed to orbital angular acceleration, which is the angular acceleration of a point particle around a fixed origin, spin angular acceleration describes the angular acceleration of a rigid body about its centre of rotation.
w(t) = w(0) + α*t
also w(0) =0
=> time = 36.8/1.51= 24.370 s
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Answer:
Volume of the sample: approximately
.
Average density of the sample: approximately
.
Assumption:
.
.- Volume of the cord is negligible.
Explanation:
<h3>Total volume of the sample</h3>
The size of the buoyant force is equal to
.
That's also equal to the weight (weight,
) of water that the object displaces. To find the mass of water displaced from its weight, divide weight with
.
.
Assume that the density of water is
. To the volume of water displaced from its mass, divide mass with density
.
.
Assume that the volume of the cord is negligible. Since the sample is fully-immersed in water, its volume should be the same as the volume of water it displaces.
.
<h3>Average Density of the sample</h3>
Average density is equal to mass over volume.
To find the mass of the sample from its weight, divide with
.
.
The volume of the sample is found in the previous part.
Divide mass with volume to find the average density.
.
Answer:
E = 2.7 x 10¹⁶ J
Explanation:
The release of energy associated with the mass can be calculated by Einstein's mass-energy relation, as follows:

where,
E = Energy Released = ?
m = mass of material reduced = 0.3 kg
c = speed of light = 3 x 10⁸ m/s
Therefore,

<u>E = 2.7 x 10¹⁶ J</u>