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3 years ago

Without his glasses, Isaac can see objects clearly only if they are less than 4.7 m from his eyes.

Physics

1 answer:

Mazyrski [523]3 years ago

6 0

Answer:

The focal length is $f = -4.721 \ m$

Explanation:

From the question we are told that

The image distance is $v = 4.7 + (2.1 *10^{-2}) = - 4.721 \ m$ the negative means image is formed behind the lens

Generally the object distance is $u = \infty$ this mean the light ray coming from the object are parallel to each other

So from lens equation

$\frac{1}{\infty } - \frac{1}{4.721} = \frac{1}{f}$

=> $f = -4.721 \ m$

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A key lime pie in a 10.00 inch diameter plate is placed upon a rotating tray. Then, the tray is rotated such that the rim of the

juin [17]

Answer:

The angular distance in revolution is $revolution = 3.439 \ revolution$

The angular distance in radians is $\theta_{rad}= 21.6 \ radians$

The angular distance in degrees is $\theta =1238.04^o$

The angular size is $Z = \frac{2}{9} \pi \ radians$

Explanation:

From the question we are told that

The diameter is $d = 10 \ inches$

The distance moved by the rim is $D = 108 \ inches$

Generally the circumference of the pie plate is mathematically represented as

$C = \pi d$

Substituting the values

$C = 10 *3.142$

$= 31.42 \ inches$

The number resolution carried out by the pie plate is evaluated as

$revolution = \frac{D}{C}$

Substituting value

$revolution = \frac{108}{31.4}$

$revolution = 3.439 \ revolution$

The angular distance $\theta_{rad}$ is mathematically evaluated as

$\theta_{rad} = \frac{D}{r}$

Where r is the radius which is mathematically evaluated as

$r = \frac{d}{2} = \frac{10}{2} = 5 \ inches$

Substituting this into the equation for angular distance

$\theta_{rad} = \frac{108}{5}$

$\theta_{rad}= 21.6 \ radians$

The angular distance traveled in degrees is

$\theta = 3.439 *360$

$\theta =1238.04^o$

When the pie is cut into 9 equal parts

The angular size would be mathematically evaluated as

$Z = \frac{2\pi}{9}$

$Z = \frac{2}{9} \pi \ radians$

7 0

4 years ago

How do you find the speed of an object given its mass and kinetic energy (what is the formula)?

madam [21]

v = √ { 2*(KE) ] / m } ;

Now, plug in the known values for "KE" ["kinetic energy"] and "m" ["mass"] ;

and solve for "v".
______________________________________________________
Explanation:
_____________________________________________________
The formula is: KE = (½) * (m) * (v²) ;
_____________________________________

"Kinetic energy" = (½) * (mass) * (velocity , "squared")
________________________________________________
Note: Velocity is similar to speed, in that velocity means "speed and direction"; however, if you "square" a negative number, you will get a "positive"; since:  a "negative" multiplied by a "negative" equals a "positive".
____________________________________________
So, we have the formula:
___________________________________
KE = (½) * (m) * (v²) ; to solve for "(v)" ; velocity, which is very similar to the "speed";
___________________________________________________
we arrange the formula ;
__________________________________________________
(KE) = (½) * (m) * (v²) ;  ↔ (½)*(m)* (v²) = (KE) ;
___________________________________________________

→ We have: (½)*(m)* (v²) = (KE) ; we isolate, "m" (mass) on one side of the equation:
______________________________________________________

→ We divide each side of the equation by: "[(½)* (m)]" ;
___________________________________________________

→ [ (½)*(m)*(v²) ] /  [(½)* (m)] = (KE) / [(½)* (m)]<span> ;
</span>______________________________________________________
to get:
______________________________________________________
→ v² =   (KE) / [(½)* (m)]

→ v² = 2 KE / m
_______________________________________________________
Take the "square root" of each side of the equation ;
_______________________________________________________
  → √ (v²) = √ { 2*(KE) ] / m }
________________________________________________________

→ v = √ { 2*(KE) ] / m } ;

Now, plug in the known values for "KE" ["kinetic energy"] and "m" ["mass"];

and solve for "v".
______________________________________________________

8 0

3 years ago

The air that flows over the top part of an airplane's wing moves faster than the air that flows across the bottom. This faster m

kaheart [24]

As an airplane moves through the air, its wings cause changes in the speed and pressure of the air moving past them. These changes result in the upward force called lift.

The Bernoulli principle states that an increase in the speed of a fluid occurs simultaneously with a decrease in the pressure exerted by the fluid.

A wing is shaped and tilted so the air moving over it moves faster than the air moving under it. As air speeds up, its pressure goes down. So the faster-moving air above exerts less pressure on the wing than the slower-moving air below. The result is an upward push on the wing—lift!

4 0

3 years ago

Which term describes the transfer of thermal energy from one object to another because of a difference in temperature? 1.energy

gregori [183]

The answer is 3.heat

6 0

3 years ago

What is the wavelength of a wave that has a speed of 3 km/s and a frequency of 12 Hz

olasank [31]

Answer:

Wavelength = 250 m

Explanation:

[ Refer to the attached file ]

6 0

4 years ago