What would be an ideal experiment to test how different types of surfaces affect friction?

HELP PLEASE!!! 30+ points!!

GarryVolchara [31]

1) 9.26 cm

Explanation:

The focal length of a plane mirror is virtually infinite. Considering the lens equation,

$\frac{1}{f}=\frac{1}{p}+\frac{1}{q}$

where f is the focal length, p is the object distance, q the image distance. If we replace f with infinity, we get

$q=-p$

The magnification equation states that

$y' = -\frac{q}{p}y$

where y is the size of the object and y' the size of the image. Substituting q=-p, we get

$y'=y$

this means that the image produced by a plane mirror is always:

- Upright (y' is positive)

- The same size as the object

In this case, we have a book of height 9.26 cm (y=9.26 cm). This means that the magnitude of the size of the image (y') will be 9.26 cm as well.

2) 22.7 cm

As we said before, due to the infinite focal length of a plane mirror,

$q=-p$

this means that the image produced by a plane mirror is always:

- Virtual (because q is negative)

- At the same distance from the mirror as the object

In this case, we have a book placed at 22.7 cm from the mirror (p=22.7 cm). This means that the magnitude of the distance of the image from the mirror (q) will be 22.7 cm as well.

3) 1.60 m/s

We said previously that the image produced by a plane mirror is always at the same distance from the mirror as the real object. This implies that whenever we move the object toward/away from the mirror, the distance p will alway remain equal to the distance q. But this also means that the object and the distance are moving toward/away from the mirror at the same speed.

Therefore, since in this case the person is moving away from the mirror at 1.60 m/s, the image will also move away at a speed of 1.60 m/s.

4 0

2 years ago

What are the two principle advantages of telescopes over eyes?

Stells [14]

Answer:

i) Telescopes can be used to view far distant objects but the human eye can't view far distant objects.

ii) Telescopes uses two convex lenses producing a magnified image while the human eye only possesses one convex lens (image seen are smaller than that viewed under telescopes)

Explanation:

The telescopes can be used to view far distant objects due to their presence of two convex lenses. The two convex lenses are the objective lens (lens closer to object) and the eye piece lens (lens closer to eye). The object to be viewed forms an intermediate image first before the final image is seen using the eye piece lens.

The human eye only possess one convex lens and as such cannot view far ranged objects.

8 0

3 years ago

a spring gun initially compressed 2cm fires a 0.01kg dart straight up into the air. if the dart reaches a height it 5.5m determi

Vikki [24]

Answer:

2697.75N/m

Explanation:

Step one

This problem bothers on energy stored in a spring.

Step two

Given data

Compression x= 2cm

To meter = 2/100= 0.02m

Mass m= 0.01kg

Height h= 5.5m

K=?

Let us assume g= 9.81m/s²

Step three

According to the principle of conservation of energy

We know that the the energy stored in a spring is

E= 1/2kx²

1/2kx²= mgh

Making k subject of formula we have

kx²= 2mgh

k= 2mgh/x²

k= (2*0.01*9.81*5.5)/0.02²

k= 1.0791/0.0004

k= 2697.75N/m

Hence the spring constant k is 2697.75N/m

7 0

2 years ago

Which statement is true about acceleration?

Ilia_Sergeevich [38]

The answer is C is think

8 0

2 years ago

What net external force is required to give a 25 kg suitcase an acceleration of 2.2 m/s2 to the right?

lapo4ka [179]

Answer:

there are two way to get mate and i gave them sepaert explation

Explanation:

55

N

Explanation:

Using Newton's second law of motion:

F

=

m

a

Force=mass

×

acceleration

F

=

25

×

2.2

F

=

55

N

So 55 Newtons are needed.

Answer link

Nam D.

Apr 6, 2018

55

N

Explanation:

We use Newton's second law of motion here, which states that,

F

=

m

a

m

is the mass of the object in kilograms

a

is the acceleration of the object in meters per second

F

=

25

kg

⋅

2.2

m/s

2

=

55

N

3 0

2 years ago