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2 years ago

Which of the following represents a convex lens? A. +f B. -di C. -f D. +di

3 answers:

7 0

F is the focal length of the lens. A positive f indicates a converging optical device, like a convex lens or a concave mirror.

Choice A

Musya8 [376]2 years ago

6 0

Answer:

(A).+f

Explanation:

Convex lens :

Convex lens is thicker at the center and thinner at the edges.

The lens which is converging it is called convex lens.

The parallel light ray pass through the lens then the light rays converges on one point that point is called focal length.

The focal length of the convex lens is positive.

So, +f represents the focal length of Convex lens.

Hence, This is the required solution.

Guest2 years ago

0 0

+f
Apex no
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2 years ago

A cyclist going downhill is accelerating at 1.2 m/s2. If the final velocity of the cyclist is 16 m/s after 10 seconds, what is t

Blababa [14]

Answer:

Initial Velocity is 4 m/s

Explanation:

What is acceleration?

It is the change in velocity with respect to time, or the rate of change of velocity.

We can write this as:

$a=\frac{\Delta v}{t}$

Where

a is the acceleration

v is velocity

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$\Delta$ is "change in"

For this problem , we are given

a = 1.2

t = 10

Putting into formula, we get:

$a=\frac{\Delta v}{t}\\1.2=\frac{\Delta v}{10}\\\Delta v = 1.2*10\\\Delta v = 12$

So, the change in velocity is 12 m/s

The change in velocity can also be written as:

$\Delta v = Final \ Velocity - Initial \ Velocity$

It is given Final Velocity = 16, so we put it into formula and find Initial Velocity. Shown Below:

$\Delta v = Final \ Velocity - Initial \ Velocity\\12=16-Initial \ Velocity\\Initial \ Velocity = 16 - 12 = 4$

hence,

Initial Velocity is 4 m/s

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3 years ago

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Mary takes 6.0 seconds to run up a flight of stairs that is 102 meters long. if mary's weight is 87 newtons, what power has mary

pentagon [3]

Thank you for posting your question here at brainly. I hope the answer will help. Below are the choices that can be found elsewhere:

<span>A. 1.5 * 10^3 Watts
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C. 3.5 * 10^2 Watts
D. 2.5 * 10^2 Watts
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2 years ago

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A slender rod is 80.0 cm long and has mass 0.370 kg . A small 0.0200-kg sphere is welded to one end of the rod, and a small 0.05

nataly862011 [7]

Answer:

1.10 m/s

Explanation:

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$v=r\omega$

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$KE=0.5I\omega^{2}$

Potential energy

PE= mgh

From the law of conservation of energy, KE=PE hence

$0.5I\omega^{2}=mgh$ where m is mass, I is moment of inertia, $\omega$ is angular velocity, g is acceleration due to gravity and h is height

Substituting m2-m1 for m and 0.5l for h, $\frac {2v}{L}$ for $\omega$ we obtain

$0.5I(\frac {2v}{L})^{2}=0.5Lg(m2-m1)$

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$v^{2}=\frac {gl^{3}(m2-m1)}{4I}$

$v=\sqrt {\frac {gl^{3}(m2-m1)}{4I}}$

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For the sphere on the left hand side, moment of inertia I

$I=m1(0.5L)^{2}$ while for the sphere on right hand side, $I=m2(0.5L)^{2}$

The total moment of inertia is therefore given by adding

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Then we obtain

$v=\sqrt {\frac {gL^{3}(m2-m1)}{4(\frac {L^{2}(M+3m1+3m2)}{12})}}=\sqrt {\frac {3gL^{3}(m2-m1)}{L^{2}(M+3m1+3m2)}}$

This is the expression of linear speed. Substituting values given we get

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2 years ago

Electric field lines always begin at _______ charges (or at infinity) and end at _______ charges (or at infinity). One could als

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Answer:

Explanation:

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(As the positive charge would move away from positive charges and would be attracted by negative ones).

So, the combination of answers that is true is b) (positive, negative, positive).

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2 years ago