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2 years ago

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A worker does 25 J of work lifting a bucket, then sets the bucket back down in the same place. What is the total net work done o

n the bucket?

1 answer:

Vera_Pavlovna [14]2 years ago

5 0

Answer:

0 J

Explanation:

As work is force times displacement, if no displacement occurs, no work occurs.

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A beam of light traveling through a liquid (of index of refraction n1 = 1.47) is incident on a surface at an angle of θ1 = 59° w

frosja888 [35]

Answer:

(a) $n_{2} = \frac{n_{1}sin\theta_{1}}{sin\theta_{2}}$

(b) $n_{2} = 1.349$

(c) $v_{1} = 2.04\times 10^{8}\ m/s$

(d) $v_{2} = 2.22\times 10^{8}\ m/s$

Solution:

As per the question:

Refractive index of medium 1, $n_{1} = 1.47$

Angle of refraction for medium 1, $\theta_{1} = 59^{\circ}$

Angle of refraction for medium 2, $\theta_{1} = 69^{\circ}$

Now,

(a) The expression for the refractive index of medium 2 is given by using Snell's law:

$n_{1}sin\theta_{1} = n_{2}sin\theta_{2}$

where

$n_{2}$ = Refractive Index of medium 2

Now,

$n_{2} = \frac{n_{1}sin\theta_{1}}{sin\theta_{2}}$

(b) The refractive index of medium 2 can be calculated by using the expression in part (a) as:

$n_{2} = \frac{1.47\times sin59^{\circ}}{sin69^{\circ}}$

$n_{2} = 1.349$

(c) To calculate the velocity of light in medium 1:

We know that:

$Refractive\ index,\ n = \frac{Speed\ of\ light\ in vacuum,\ c}{Speed\ of\ light\ in\ medium,\ v}$

Thus for medium 1

$n_{1} = \frac{c}{v_{1}$

$v_{1} = \frac{c}{n_{1} = \frac{3\times 10^{8}}{1.47} = 2.04\times 10^{8}\ m/s$

(d) To calculate the velocity of light in medium 2:

For medium 2:

$n_{2} = \frac{c}{v_{2}$

$v_{2} = \frac{c}{n_{1} = \frac{3\times 10^{8}}{1.349} = 2.22\times 10^{8}\ m/s$

5 0

3 years ago

Read 2 more answers

If a mass of .343 kg moves down a 5m ramp in 5.8 seconds, what is the velocity and KE developed by the moving mass

Soloha48 [4]

Velocity 0.86m/s

0.13J

Explanation:

Given parameters:

Mass = 0.343kg

distance = 5m

time taken = 5.8s

Unknown:

Velocity of mass = ?

Kinetic energy = ?

Solution:

Velocity is the rate of change of displacement with time. It is a vector quantity that shows magnitude and direction.

Mathematically;

Velocity = $\frac{displacement}{time}$

Velocity = $\frac{5}{5.8 }$ = 0.86m/s

Kinetic energy is the energy due to the motion of a body. It is expressed mathematically as:

Kinetic energy = $\frac{1}{2} m v^{2}$

m is the mass

v is the velocity

Kinetic energy = $\frac{1}{2 } x 0.343 x 0.86^{2}$ = 0.13J

learn more:

Kinetic energy brainly.com/question/6536722

#learnwithBrainly

7 0

3 years ago

Solve 1 for x if a=-9.8, v=2.7, and t= 35

aliina [53]

Explanation:

x=VT+at²/2

x=2.7x35+9.8x(35)²/2

x=6097

6 0

3 years ago

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Windmills are used to convert wind energy into a more useful form. In most cases, there are three

sdas [7]

The kinetic energy of the wind ==> causes ==>
   the windmill to turn (mechanical energy) ==>
   which is used to turn an electric generator ==>
      which generates electrical energy.

4 0

3 years ago

Which increases the work output of a machine?

Dafna11 [192]

A reducing friction

3 0

3 years ago