We are making an estimate based on a scene from a fictional story. We don't know the details of the star or the spacecraft. We also don't know if the sail is completely reflective, but we'll assume that it is. We'll find the net force exerted on the spacecraft and then use Newton's second law to find the direction of the acceleration. To find the net force, identify the source and direction of each force. Choose as many as apply. a. Light delivers momentum to the sail, much like a ball thrown at a wall delivers momentum to the wall. The ball's change in momentum is directed away from the wall, so the force on the ball is also directed away from the wall. By Newton's third law, then, the force on the wall is away from the person throwing the ball.
b. The spacecraft's thrusters are directed away from the star.
c. This spacecraft is propelled only by its sail.
d. The star's gravity is directed toward the star.
e. The star's light is directed away from the star.
f. The star's wind is directed away from the star.

Chapter 23, problem 075 the figure shows a geiger counter, a device used to detect ionizing radiation (radiation that causes ionization of atoms). the counter consists of a thin, positively charged central wire surrounded by a concentric, circular, conducting cylindrical shell with an equal negative charge. thus, a strong radial electric field is set up inside the shell. the shell contains a low-pressure inert gas. a particle of radiation entering the device through the shell wall ionizes a few of the gas atoms. the resulting free electrons (e) are drawn to the positive wire. however, the electric field is so intense that, between collisions with gas atoms, the free electrons gain energy sufficient to ionize these atoms also. more free electrons are thereby created, and the process is repeated until the electrons reach the wire. the resulting "avalanche" of electrons is collected by the wire, generating a signal that is used to record the passage of the original particle of radiation. suppose the radius of the central wire is 24 âµm, the inner radius of the shell 2.3 cm, and the length of the shell 14 cm. if the electric field at the shell's inner wall is 2.8 ă— 104 n/c, what is the total positive charge on the central wire?

However, had it been a real sound, the sound's pitch would have been increased by the doppler effect, since the falcon was moving the source of the sound. perpendicular to away from towards at the same speed as

Assume that a person skiing high in the mountains at an altitude of h = 15100 ft takes in the same volume of air with each breath as she does while walking at sea level. determine the ratio of the mass of oxygen inhaled for each breath at this high altitude compared to that at sea level. assume that the air composition (i.e. % of air that is oxygen) is the same at sea level as it is at 15100 ft.