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4 years ago

What are some examples of helpful and unhelpful frictions?

1 answer:

8 0

Helpful friction would be the friction on something that you wanted to stop (a car) while unhelpful friction is friction on something that you want to keep going (a curling rock)

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A 10-turn coil of wire having a diameter of 1.0 cm and a resistance of 0.50 Ω is in a 1.0 mT magnetic field, with the coil orien

n200080 [17]

Answer:

The voltage across the capacitor is 1.57 V.

Explanation:

Given that,

Number of turns = 10

Diameter = 1.0 cm

Resistance = 0.50 Ω

Capacitor = 1.0μ F

Magnetic field = 1.0 mT

We need to calculate the flux

Using formula of flux

$\phi=NBA$

Put the value into the formula

$\phi=10\times1.0\times10^{-3}\times\pi\times(0.5\times10^{-2})^2$

$\phi=7.85\times10^{-7}\ Tm^2$

We need to calculate the induced emf

Using formula of induced emf

$\epsilon=\dfrac{d\phi}{dt}$

Put the value into the formula

$\epsilon=\dfrac{7.85\times10^{-7}}{dt}$

Put the value of emf from ohm's law

$\epsilon =IR$

$IR=\dfrac{7.85\times10^{-7}}{dt}$

$Idt=\dfrac{7.85\times10^{-7}}{R}$

$Idt=\dfrac{7.85\times10^{-7}}{0.50}$

$Idt=0.00000157=1.57\times10^{-6}\ C$

We know that,

$Idt=dq$

$dq=1.57\times10^{-6}\ C$

We need to calculate the voltage across the capacitor

Using formula of charge

$dq=C dV$

$dV=\dfrac{dq}{C}$

Put the value into the formula

$dV=\dfrac{1.57\times10^{-6}}{1.0\times10^{-6}}$

$dV=1.57\ V$

Hence, The voltage across the capacitor is 1.57 V.

5 0

3 years ago

A triangle has two sides of length 10 cm and 14 cm. what can you say about the length of the third side?

Anton [14]

A side of any triangle is less than the sum of the other two sides so the third side must be less than 24cm.

<h3>What is a triangle?</h3>

A triangle is a 3-sided shape that is occasionally referred to as a triangle. There are three sides and three angles in every triangle, some of which may be the same.

The sum of all three angles inside a triangle will be 180° and the area of a triangle is given as (1/2) × base × height.

There are many types of triangles such that right-angle triangles, equilateral triangles, and much more.

In any triangle, the sum of two sides is always greater than the third side.

If the third side is equal to the sum of two sides then it will be a straight line rather than a triangle.

It means 10 + 14 > third side

24 cm > third side

Hence "A side of any triangle is less than the sum of the other two sides so the third side must be less than 24cm".

For more about triangles,

brainly.com/question/2773823

#SPJ4

3 0

1 year ago

If anyone don't mind answering-:

Dennis_Churaev [7]

Answer:

1. inference

2. analysis

others I don't have any idea sorry

5 0

3 years ago

What happens to the distance physics help please? The frequency of a wave increases. What happens to the distance between succes

aliya0001 [1]

For any periodic wave
v = f λ 

where 
v = velocity 
f = frequency 
λ = wavelength (distance between 2 successive crests) 

This means that 
λ = v/f 

Assuming that v stays the same while f increases, λ must DECREASE.

I hope this helps

4 0

3 years ago

You are an evolutionary biologist studying a population of bats in the rain forest in Brazil. Most of the population possesses m

Oxana [17]

Answer:

Option (B)

Explanation:

In the stabilizing natural selection, the extreme traits from both the ends are eliminated by natural selection and natural selection favors the intermediate trait. So over time individuals having the intermediate traits are selected over the individuals having extreme traits.

So here the population of the bat which possesses moderate wing length is selected over the individual with extreme traits like individuals with short wings and long wings. As a result, the population of moderate length wing bats increased.

Therefore the correct answer is (B)- stabilizing natural selection.

3 0

3 years ago