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Vanyuwa [196]
3 years ago
12

A body travels the first half of the total distance with velocity v and second half with v2 calculate avg velocity

Physics
1 answer:
LuckyWell [14K]3 years ago
8 0

Answer:

v = 2 v₁ v₂ / (v₁ + v₂)

Explanation:

The body travels the first half of the distance with velocity v₁.  The time it takes is:

t₁ = (d/2) / v₁

t₁ = d / (2v₁)

Similarly, the body travels the second half with velocity v₂, so the time is:

t₂ = (d/2) / v₂

t₂ = d / (2v₂)

The average velocity is the total displacement over total time:

v = d / t

v = d / (t₁ + t₂)

v = d / (d / (2v₁) + d / (2v₂))

v = d / (d/2 (1/v₁ + 1/v₂))

v = 2 / (1/v₁ + 1/v₂)

v = 2 / ((v₁ + v₂) / (v₁ v₂))

v = 2 v₁ v₂ / (v₁ + v₂)

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Answer:

1)

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F=qvB sin \theta

where here:

For the proton in this problem:

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v = 300 m/s is the speed of the proton

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So the force is

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2)

The magnetic field produced by a bar magnet has field lines going from the North pole towards the South Pole.

The density of the field lines at any point tells how strong is the magnetic field at that point.

If we observe the field lines around a magnet, we observe that:

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- The density of field lines is lower far from the Poles

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3)

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It can be applied as follows:

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4)

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r=\frac{mv}{qB}

where here we have:

m=6.64\cdot 10^{-22} kg is the mass of the alpha particle

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5)

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f=\frac{qB}{2\pi m}

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6)

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7)

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8)

The flux is calculated as

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\Phi = (5.5)(0.012)(sin 18^{\circ})=0.021 Wb

See the last 7 answers in the attached document.

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