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** Space travel A pilot and her spaceship have a mass of 400 kg. The pilot expects to live 50 more Earth years and wishes to travel to a star that requires 100 years to reach even if she were to travel at the
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- An astronaut wishes to visit the Andromeda galaxy, making a one-way trip that will take 30.0 years in the space-ships frame of reference. Assume the galaxy is 2.00 million light-years away and his speed is constant. (a) How fast must he travel relative to Earth? (b) What will be the kinetic energy of his spacecraft, which has mass of 1.00 106 kg? (c) What is the cost of this energy if it is purchased at a typical consumer price for electric energy, 13.0 cents per kWh? The following approximation will prove useful: 11+x1x2forx1arrow_forwardIntegrated Concepts A 2.50-kg fireworks shell is fired straight up from a mortar and reaches a height of 110 m. (a) Neglecting air resistance (a poor assumption, but we will make it for this example), calculate the shell's velocity when it leaves the mortar. (b) The mortar itself is a tube 0.450 m long. Calculate the average acceleration of the shell in the tube as it goes from zero to the velocity found in (a). (c) What is the average force on the shell in the mortar? Express your answer in newtons and as a ratio to the weight of the shell.arrow_forward(a) Calculate the speed of a 1.00- g particle of dust that has the same momentum as a proton moving at 0.999c. (b) What does the small speed tell us about the mass of a proton compared to even a tiny amount of macroscopic matter?arrow_forward
- Professional Application Ion-propulsion rockets have been proposed for use in space. They employ atomic ionization techniques and nuclear energy sources to produce extremely high exhaust velocities, perhaps as great as 8.00106 m/s. These techniques allow a much more favorable payload-to-fuel ratio. To illustrate this fact: (a) Calculate the increase in velocity of a 20,000-kg space probe that expels only 40.0-kg of its mass at the given exhaust velocity. (b) These engines are usually designed to produce a very small thrust for a very long time—the type of engine that might be useful on a trip to the outer planets, for example. Calculate the acceleration of such an engine if it expels 4.50106 kg/s at the given velocity, assuming the acceleration due to gravity is negligible.arrow_forwardWhat is the velocity of an electron that has a momentum of 3.041021kgm/s ? Note that you must calculate the velocity to at least four digits to see the difference from c.arrow_forwardDoes the kinetic energy of an object depend on the frame of reference in which its motion is measured? Provide an example to prove this point.arrow_forward
- Two astronauts at rest face each other in space. One, with mass m1, throws a ball of mass mb the other, whose mass is m2. She catches the ball and throws is back to the first astronaut following each throw the ball has a speed of v relative to the thrower. Let the direction that Astronaut 1 first throw the ball to the positive direction. After each has made one throw and one catch how fast are the astronauts moving? How much has the two-astronaut system’s kinetic energy changed Where did the energy come from?arrow_forwardA 110-kilogram tackler traveling at 2.5 m/s makes a head-on collision with and successfully carries an 88-kilogram halfback traveling at 5.0 m/s. Part A How fast will they be going together just after they smash into each other? Include the correct units and round your result to two major numbers. Submit 31 Value = v' Units Requested: Oarrow_forwardA 44kg girl skates at 1.5m/s on ice toward her 81kg friend who is standing still with open arms. As they collide and hold each other what is the speed of the couple to one decimal placearrow_forward
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