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3 years ago

7

An oil droplet is levitated and held at rest in a region where the electric field is 1.4x104 N/C directed vertically downwards.

If the droplet has 3 excess electrons attached, what is its mass

1 answer:

Ratling [72]3 years ago

8 0

W = m g weight of drop

W = q E

m = q E / g = = 3 e E / g

m = 3 * 1.6E-19 * 1.4E4 / 9.8 = 6.96E-16 kg

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What are 3 criteria for acceleration?

Temka [501]

I don't think you mean 'criteria'. I think you mean three occurrences or
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They are:

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-- an object is slowing down
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Any one of these changes is acceleration.

There's a single term that covers them all. It is "change in velocity".

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3 years ago

An airplane travels at 300 mi/h south for 2.00 h and then at 250 mi/h north for 750 miles. what is the average speed for the tri

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3 years ago

E14. A ball rolls off a table with a horizontal velocity of 5 m/s. If

Shkiper50 [21]

a) Vertical velocity: 5.9 m/s

b) Horizontal velocity: 5 m/s

Explanation:

a)

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- A uniformly accelerated motion (constant acceleration) along the vertical direction

Here we want to find the vertical component of the ball's velocity. This can be done by using the suvat equation for the vertical motion:

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where:

$v_y$ is the vertical velocity at time t

$u_y=0$ is the initial vertical velocity (zero because the ball has been thrown horizontally)

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b)

The motion along the vertical direction is an accelerated motion, because there is a force (the force of gravity) acting on the ball and that it causes an acceleration in the ball.

However, there are no forces acting in the horizontal direction on the ball (if we neglect the air resistance): this means that the acceleration of the ball in the horizontal direction is zero.

As a consequence, this also means that the horizontal component of the ball's velocity is constant during the motion.

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4 years ago

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Pani-rosa [81]

Answer:

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3 years ago

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olya-2409 [2.1K]

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3 years ago