Concept explainers
The three type of forces acting on the sail.
Answer to Problem 74PQ
The gravitational force acting on the sail is
Explanation of Solution
Write the expression for the force of gravitation acting on the sail.
Here,
Write the expression for the drag force on the sail.
Here,
Write the expression for the orbital velocity of the sail.
Here,
Write the value for distance between Earth and sail.
Write the expression for the force exerted by the solar radiations on the sail.
Here,
Conclusion:
Substitute
Substitute
Substitute
Substitute
Therefore, the gravitational force acting on the sail is
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Chapter 34 Solutions
EBK PHYSICS FOR SCIENTISTS AND ENGINEER
- One of the highest power lasers in the world sits on a table. It emits pulses that last approximately 16 fs, and contain 103 mJ of energy. "fs" indicates a femtosecond, which is 10-15 seconds. a) What is the average power associated with a single pulse? b) What is the physical length of this pulse? c) When the beam exits the laser, it is approximately 30 mm in diameter. Molecules begin to ionize when applied electric fields reach approximately 8.680e+09 V/m. To what diameter must the beam be focused to reach this electric field strength?arrow_forwardThe Earth has a radius of 6.38×10^6m and is 1.50×10^11m from the sun. The intensity of sunlight at Earth’s orbit is 1390W/m2. a) What is the intensity of sunlight at Neptune’s orbit, a distance of 4.5×10^12m from the sun? b) What is the total power radiated by the Sunarrow_forwardOptical tweezers use light from a laser to move single atoms and molecules around. Suppose the intensity of light from the tweezers is 1.00 103 W/m2, the same as the intensity of sunlight at the surface of the Earth. a. What is the pressure on an atom if light from the tweezers is totally absorbed? b. If this pressure were exerted on a hydrogen atom, what would be its acceleration? Assume the cross-sectional area is 6.65 1029 m2.arrow_forward
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- Auroras are caused by collisions between particles such as electrons released by the Sun, and atoms in a planet’s atmosphere. These collisions transfer energy to the atmospheric atoms causing them to emit specific colors (wavelengths) of light. On Earth, auroras occur in a layer of the atmosphere known as the ionosphere, 80 km to 400 km above the surface. If solar activity increases, the number of sunspots increases, and more particles are released by the Sun. If, on average, there were 150 sunspots in 2014, 5 in 2020, and 160 in 2023, which year(s) will have the most auroras, and which year(s) the least? Can you explain why? Answer:arrow_forwardA possible means of space flight is to place a perfectly reflecting aluminized sheet into orbit around the Earth and then use the light from the Sun to push this "solar sail." Suppose a sail of area A = 5.20 x 105 m² and mass m = 6,200 kg is placed in orbit facing the Sun. Ignore all gravitational effects and assume a solar intensity of 1,370 W/m². (a) What force (in N) is exerted on the sail? (Enter the magnitude.) N (b) What is the sail's acceleration? (Enter the magnitude in µm/s².) μm/s² (c) Assuming the acceleration calculated in part (b) remains constant, find the time interval (in days) required for the sail to reach the Moon, 3.84 x 108 m away, starting from rest at the Earth. days (d) What If? If the solar sail were initially in Earth orbit at an altitude of 340 km, show that a sail of this mass density could not escape Earth's gravitational pull regardless of size. (Calculate the magnitude of the gravitational field in m/s².) m/s² (e) What would the mass density (in kg/m²) of…arrow_forwardYou are standing 4.0 m from a 200-W lightbulb. If the pupil of your eye is a circle 8.0 mm in diameter, how much energy enters your eye per second?arrow_forward
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