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
kherson [118]
3 years ago
12

Suppose you designed a spacecraft to work by photon pressure. The sail was a completely absorbing fabric of area 1.0 km2 and you

directed a laser beam of wavelength 650 nm onto it at a rate of 1 mol of photons per second from a base on the moon. The spacecraft has a mass of 1.0 kg. Given that, after a period of acceleration from standstill, speed = (force/mass) x time, how many minutes would it take for the craft to accelerate to a speed of 1.0 m/s (about 2.2 mph)?
Physics
1 answer:
Alekssandra [29.7K]3 years ago
4 0

Answer:

(a) F = 6.14 *10⁻⁴ N

(b) P = 6.14* 10⁻¹⁰ Pa

(c) t = 27.2 min

Explanation:

Area of sail A = 1.0 km² = 1.0 * 10⁶m²

Wavelength of light  λ = 650 nm = 650 * 10⁻⁹ m

Rate of impact of photons R = 1 mol/s = 6.022 * 10²³ photons/s

(a)

Momentum of each photon is Ρ = h/λ = 6.625 * 10⁻³⁴ / 650 * 10⁻⁹

      = 1.0192 * 10⁻²⁷ kg.m/s

Since the photons are absorbed completely, in every collision the above momentum is transferred to the sail.  

Momentum transferred to the sail per second is product of rate of impact of photons and momentum transferred by each photon.

dp/dt = R * h/ λ

This is the force acting on the sail.

F = R * h/λ = 6.022 * 10²³ * 1.0192 * 10⁻²⁷ = 6.14 *10⁻⁴ N

F = 6.14 *10⁻⁴ N

b)

Pressure exerted by the radiation on the sail = Force acting on the sail / Area of the sail

P = F/A =  6.14 * 10⁻⁴ / 1.0 * 10⁶ =  6.14* 10⁻¹⁰ Pa

P = 6.14* 10⁻¹⁰ Pa

c)  

Acceleration of spacecraft a = F/m = 6.14 * 10⁻⁴ /1.0 = 6.14 * 10⁻⁴m/s²

As the spacecraft starts from rest, initial speed u=0,m/s ,

final speed is u = 1.0 m/s after time t  

v = u+at  

t = 1.0 - 0/ 6.14 * 10⁻⁴ =  1629s = 27.2 min

t = 27.2 min

You might be interested in
How does an atom of bromine-79 become a bromide ion with a -1 charge?
Tanzania [10]

a the atom loses 1 proton to have a total of 34

3 0
3 years ago
If a 50 kg student is standing on the edge of a cliff. Find the student’s gravitational potential energy if the cliff is 40 m hi
Oduvanchick [21]

you can find it using the equation: potential energy=mass*gravitational acceleration*height.


energy=50kg*9.8N/kg*40m=19600Nm=19600J or 19.6kJ


Sometimes they use 10 instead of 9.8 for the g constant. 


Rember to make me Brainliest!!!

3 0
3 years ago
Which of the following is an accurate description of synaptic pruning?
Lemur [1.5K]

Answer options:

A) Some connections are lost because critical stages of development were missed.

B) Some connections are lost so others can be strengthened.

C) Some connections are lost because of experimentation with drugs or alcohol.

D) Some connections are lost so that children become less dependent and are less tied to their parents.

Answer:

B) Some connections are lost so others can be strengthened.

Explanation:

Synaptic pruning refers to a natural process that occurs in the brain between childhood and adulthood. Extra synaptic connections are eliminated in order to increase the efficiency of neuronal communications. It is thought to be the brain’s way of removing connections that are no longer needed.

6 0
2 years ago
A student standing on a cliff that is a vertical height d = 8.0 m above the level ground throws a stone with velocity v0 = 24 m/
PilotLPTM [1.2K]

Answer:

a) Vf = 27.13 m/s

b) It would have been the same

Explanation:

On the y-axis:

Y=-Vo*sin\theta*t-1/2*g*t^2

-8=-24*sin(21)*t-1/2*10*t^2

Solving for t:

t1 = 0.67s     t2= -2.4s

Discarding the negative value and using the positive one to calculate the velocity:

Vf_y = -Vo*sin\theta-g*t

Vf_y = -15.3m/s

So, the module of the velocity will be:

Vf=\sqrt{(-15.3)^2+(24*cos(21))^2}

Vf=27.13m/s

If you throw it above horizontal, it would go up first, and when it reached the initial height, the velocity would be the same at the throwing instant. And starting then, the movement will be the same.

3 0
3 years ago
When a metal reacts with a non-metal it forms what???​
Snezhnost [94]

Answer:

When metals react with non-metals, electrons are transferred from the metal atoms to the non-metal atoms, forming ions. The resulting compound is called an ionic compound.

:

5 0
3 years ago
Other questions:
  • Generators use the magnetic field of which of the following to produce an electric current?
    12·1 answer
  • An airplane accelerates down a runway at 3 m/s2 for 32 s until is finally lifts off the ground. Determine the distance traveled
    7·1 answer
  • Helpppp!! On which surface is the student not able to move the box?
    6·1 answer
  • In a cloud chamber experiment, a proton enters a uniform 0.260 T magnetic field directed perpendicular to its motion. You measur
    7·1 answer
  • 20) A 5 Kg watermelon is dropped off a 10 meter balcony. What will the watermelon's velocity be right before it hits the ground?
    6·1 answer
  • Explain why air is not used as a<br>brake fluid ​
    10·1 answer
  • Define a combination circuit.
    12·1 answer
  • 1.00 x 10^8 kg of clear liquid (specific heat
    7·1 answer
  • A metre rule is used to measure a length. Which reading is shown to the nearest millimetre? A 0.7m B 0.76m C 0.761m D 0.7614m
    5·2 answers
  • Both Newton's Law of Universal Gravitation and Coulomb's Law follow the ...
    8·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!