1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
enyata [817]
3 years ago
9

LASIK eye surgery uses pulses of laser light to shave off tissue from the cornea, reshaping it. A typical LASIK laser emits a 1.

0-mm-diameter laser beam with a wavelength of 193 nm. Each laser pulse lasts 14 ns and contains 2.0 mJ of light energy. Part A What is the power of one laser pulse
Physics
1 answer:
Fittoniya [83]3 years ago
3 0

Answer:

143 kW

Explanation:

Given that

Diameter of the beam, d = 1 mm

Wavelength of the beam, λ = 193 nm

Time used by the pulse, t = 14 ns

Energy of the pulse, U = 2 mJ

Recall that Power can be mathematically calculated using the relation,

Power = Work Done / Time,

To solve this, we apply the formula

P = U / Δt

P = 2*10^-3 J / 14*10^-9 s

P = 142857 W

P = 143 kW

You might be interested in
A fire breaks out and increases the Kelvin temperature of a cylinder of compressed gas by a factor of 2.4. What is the final pre
kherson [118]

Answer:

P(final) is 2.4 times P(initial).

Explanation:

Here we can assume that the cylinder did not break and it's volume and number of moles of gas present in the cylinder remains constant.

Given the temperature increases by a factor of 2.4. Let us assume that the initial temperature be T_{1} and the final temperature be T_{2}.

Given that T_{2}=2.4\times T_{1}

Now we know the ideal gas equation is PV=nRT

here V=constant , n=constant , R=gas constant(which is constant).

\frac{P}{T}=constant

\frac{P_{1} }{T_{1}}=\frac{P_{2} }{T_{2} }

P_{2}=(\frac{T_{2} }{T_{1} } )P_{1}

P_{2}=(\frac{2.4T_{1} }{T_{1} } )P_{1}

P_{2}=2.4\times P_{1}

7 0
3 years ago
3) A driver in a 1000-kg car traveling at 24 m/s slams on the brakes and skids to a stop. If the coefticient of friction between
Natali5045456 [20]

Answer:

A) 37 m

Explanation:

The car is moving of uniformly accelerated motion, so the distance it covers can be calculated by using the following SUVAT equation:

v^2 -u^2 = 2ad (1)

where

v = 0 m/s is the final velocity of the car

u = 24 m/s is the initial velocity

a is the acceleration

d is the length of the skid

We need to find the acceleration first. We know that the force responsible for the (de)celeration is the force of friction, so:

F=ma=-\mu mg

where

m = 1000 kg is the mass of the car

\mu = 0.80 is the coefficient of friction

a is the deceleration of the car

g = 9.8 m/s^2 is the acceleration due to gravity

The negative sign is due to the fact that the force of friction is against the motion of the car, so the sign of the acceleration will be negative because the car is slowing down. From this equation, we find:

a=-\mu g

And we can substitute it into eq.(1) to find d:

v^2 -u^2 = 2(\-mu g) d\\d= \frac{v^2-u^2}{-2 \mu g}=\frac{0-(24 m/s)^2}{-2(0.80)(9.8 m/s^2)}=36.7 m \sim 37 m

7 0
3 years ago
Which direction will thermal energy flow if you pick up a snowball with your bare hand? Thermal energy will flow from the snowba
Lapatulllka [165]

Answer:

b. Thermal energy will flow from your hand to the snowball.

Explanation:

4 0
3 years ago
Read 2 more answers
Starting from rest, a disk rotates about its central axis with constant angular acceleration. In 5.00 s, it rotates 13.9 rad. Du
alisha [4.7K]

Answer:

(a) Angular acceleration is 1.112 rad/s².

(b) Average angular velocity is 2.78 rad/s .

Explanation:

The equation of motion in Rotational kinematics is:

θ = θ₀ + 0.5αt²

Here θ is angular displacement at time t, θ₀ is angular displacement at time t=0, t is time and α is constant angular acceleration.

(a) According to the problem, θ is 13.9 rad, θ₀ is zero as it is at rest and t is 5 s. Put these values in the above equation:

13.9 = 0 + 0.5α(5)²

α = 1.112 rad/s²

(b) The equation of average angular velocity is:

ω = Δθ/Δt

ω = \frac{13.9}{5}

ω = 2.78 rad/s

3 0
3 years ago
Complex carbohydrates, such as _____ and _____, provide the body with long-lasting energy.
Sauron [17]

complex carbohydrates, such as starches and fiber, provide the body with long-lasting energy.

Hope this helps!

7 0
3 years ago
Read 2 more answers
Other questions:
  • Determine the frequency of light whose wavelength is 4.257 x 10-7 cm
    13·1 answer
  • !!PLEASE ANSWER ASAP!!
    12·2 answers
  • A tennis player tosses a tennis ball straight up and then catches it after 2.00 s at the same height as the point of release. (a
    9·1 answer
  • Explain why it is important that there is only one possible explanation for experimental data.
    14·1 answer
  • HELP is it impossible to experience free fall near the earths surface? why?
    7·1 answer
  • Which until is commonly used to measure density
    7·2 answers
  • How does object float
    8·2 answers
  • Yes ples omggggggggg
    14·2 answers
  • What causes the phenomenon of "red shift" and "blue shift" in astronomy? *
    9·2 answers
  • Why should people pay attention to scientists when making decisions?
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!