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4 years ago

Hi :) I don’t really understand why it’s A

Physics

1 answer:

Troyanec [42]4 years ago

6 0

Answer:

Explanation:

1. When the block moves across a table top, F(pulling) = - F(frictional).

Sum of this forces = 0, so the block moves with uniform speed.

2. When the block is pulled on top of the table covered with beads

F(pulling) > - F(frictional).

So, the sum of forces (∑F) is a number that is more than 0 and directed to the direction of movement.

So, a = ∑F / m is positive and constant. Speed is increasing because

v(t) = v(0)+at

a is constant and directed forward.

That means a is acceleration, and constant.

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Find the self-inductance of a 1700-turn solenoid 55 cm long and 4.0 cm in diameter. Express your answer with the appropriate uni

Nitella [24]

The self-inductance of the solenoid is 8.25 mH.

The given parameters;

number of turns, N = 1700 turn
length of the solenoid, l = 55 cm = 0.55 m
diameter of solenoid, d = 4 cm
radius of the solenoid, r = 2 cm = 0.02 m

The area of the solenoid is calculated as follows;

$A = \pi r^2\\\\A = \pi \times (0.02)^2\\\\A = 0.00125 \ m^2$

The self-inductance of the solenoid is calculated as follows;

$L = \frac{\mu_o N^2 A }{l} \\\\L = \frac{(4\pi \times 10^{-7}) \times 1700^2 \times 0.00125}{0.55} \\\\L = 0.00825 \ H\\\\L = 8.25\ mH$

Thus, the self-inductance of the solenoid is 8.25 mH.

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3 years ago

How long does it take light to travel from jupiter to earth?.

valentina_108 [34]

The answer is : 35 to 52 minutes.
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3 years ago

When an object is moving with uniform circular motion, the centripetal acceleration of the object a. is circular. b. is perpendi

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Hi Pupil Here's Your answer :::

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When an object is moving with uniform circular motion, the centripetal acceleration of the object $\textbf{is\:Zero}$ .

Because the body is moving with a uniform velocity and hence, there might not be any acceleration due to it.

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3 years ago

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<h3>Explanation:</h3>

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