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hram777 [196]
3 years ago
6

If 34.7 g of O2 reacts with iron to form 79.34 g of iron oxide, how much iron was used in the reaction?

Physics
1 answer:
zhuklara [117]3 years ago
6 0

Answer: B. 44.64 g

Explanation:

According to the law of conservation of mass, mass can neither be created nor be destroyed. Thus the mass of products has to be equal to the mass of reactants. The number of atoms of each element has to be same on reactant and product side. Thus chemical equations are balanced.

Mass of reactants = mass of iron + mass of oxygen = mass of iron + 34.7 g

Mass of product = mass of iron oxide = 79.34 g

As Mass of reactants = Mass of product

mass of iron + 34.7 g = 79.34 g

mass of iron = 44.64 g

Thus 44.64 g of iron was used in the reaction

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Answer:

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Explanation:

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q = 1.6 × 10⁻¹⁹ C

m = 9.11 x 10⁻³¹ kg

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v_0 = \sqrt{\dfrac{1.6 \times 10^{-19}\times 1.1 \times 10^{3}\times 0.06}{0.0412\times 9.11 \times 10^{-31} }(\dfrac{0.06}{2}+0.12)}

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B_0 = \dfrac{E}{v_0}

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B_0 = 1.69 \times 10^{-4}\ T

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3 years ago
A man walks along a straight path at a speed of 4 ft/s. A searchlight is located on the ground 6 ft from the path and is kept fo
BARSIC [14]

We are given that,

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Differentiating each side with respect to t, we get,

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\frac{dx}{dt} = (6sec^2\theta)\cdot \frac{d\theta}{dt}

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Replacing the value of the velocity

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cos\theta = \frac{6}{10}

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3 years ago
Choose all the answers that apply.
Serhud [2]
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8 0
3 years ago
A 50.0 kg crate is pulled 375 N of force applied to a rope. The crate slides without friction.
LUCKY_DIMON [66]

Hi there!

We can use the work-energy theorem to solve.

Recall that:

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The initial kinetic energy is 0 J because the crate begins from rest, so we can plug in the given values for mass and final velocity:

W = \frac{1}{2}(50)(5.61^2) = 786.8025 J

Now, we can define work:

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Now, plug in the values:

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2 years ago
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This question can be solved using the concept of friction energy.

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7 0
2 years ago
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