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please assume the free-fall acceleration \(g=9.80 \mathrm{m} / \mathrm{s}^{2}\) unless a more precise value is given in the problem statement. Ignore air resistance. You drop a stone into a deep well and hear it hit the bottom 3.20 s later. This is the time it takes for the stone to fall to the bottom of the well, plus the time it takes for the sound of the stone hitting the bottom to reach you. Sound travels about \(343 \mathrm{m} / \mathrm{s}\) in air. How deep is the well?

In the problems, please assume the free-fall acceleration $g=9.80 \mathrm{m} / \mathrm{s}^{2}$ unless a more precise value is given in the problem statement. Ignore air resistance. 56\. (a) If a freestyle swimmer traveled \(1500 \mathrm{m}\) in a time of $14 \mathrm{min} 53 \mathrm{s},$ how fast was his average speed? (b) If the pool was rectangular and \(50 \mathrm{m}\) in length, how does the speed you found compare with his sustained swimming speed of \(1.54 \mathrm{m} / \mathrm{s}\) during one length of the pool after he had been swimming for 10 min? What might account for the difference?

In the problems, please assume the free-fall acceleration $g=9.80 \mathrm{m} / \mathrm{s}^{2}$ unless a more precise value is given in the problem statement. Ignore air resistance. A cheetah can accelerate from rest to \(24 \mathrm{m} / \mathrm{s}\) in $2.0 \mathrm{s}$ Assuming the acceleration is constant over the time interval, (a) what is the magnitude of the acceleration of the cheetah? (b) What is the distance traveled by the cheetah in these \(2.0 \mathrm{s} ?\) (c) A runner can accelerate from rest to \(6.0 \mathrm{m} / \mathrm{s}\) in the same time, $2.0 \mathrm{s} .$ What is the magnitude of the acceleration of the runner? By what factor is the cheetah's average acceleration magnitude greater than that of the runner?

In the problems, please assume the free-fall acceleration $g=9.80 \mathrm{m} / \mathrm{s}^{2}$ unless a more precise value is given in the problem statement. Ignore air resistance. A rocket is launched from rest. After 8.0 min, it is \(160 \mathrm{km}\) above the Earth's surface and is moving at a speed of $7.6 \mathrm{km} / \mathrm{s} .$ Assuming the rocket moves up in a straight line, what are its (a) average velocity and (b) average acceleration?

In the problems, please assume the free-fall acceleration $g=9.80 \mathrm{m} / \mathrm{s}^{2}$ unless a more precise value is given in the problem statement. Ignore air resistance. A streetcar named Desire travels between two stations \(0.60 \mathrm{km}\) apart. Leaving the first station, it accelerates for \(10.0 \mathrm{s}\) at $1.0 \mathrm{m} / \mathrm{s}^{2}$ and then travels at a constant speed until it is near the second station, when it brakes at \(2.0 \mathrm{m} / \mathrm{s}^{2}\) in order to stop at the station. How long did this trip take? [Hint: What's the average velocity?]

In the problems, please assume the free-fall acceleration $g=9.80 \mathrm{m} / \mathrm{s}^{2}$ unless a more precise value is given in the problem statement. Ignore air resistance. A stone is thrown vertically downward from the roof of a building. It passes a window \(16.0 \mathrm{m}\) below the roof with a speed of $25.0 \mathrm{m} / \mathrm{s} .\( It lands on the ground \)3.00 \mathrm{s}$ after it was thrown. What was (a) the initial velocity of the stone and (b) how tall is the building?

In the problems, please assume the free-fall acceleration $g=9.80 \mathrm{m} / \mathrm{s}^{2}$ unless a more precise value is given in the problem statement. Ignore air resistance. A car traveling at \(29 \mathrm{m} / \mathrm{s}(65 \mathrm{mi} / \mathrm{h})\) runs into a bridge abutment after the driver falls asleep at the wheel. (a) If the driver is wearing a seat belt and comes to rest within a 1.0 -m distance, what is his acceleration (assumed constant)? (b) A passenger who isn't wearing a seat belt is thrown into the windshield and comes to a stop in a distance of \(10.0 \mathrm{cm} .\) What is the acceleration of the passenger?

In the problems, please assume the free-fall acceleration $g=9.80 \mathrm{m} / \mathrm{s}^{2}$ unless a more precise value is given in the problem statement. Ignore air resistance. To pass a physical fitness test, Marcella must run \(1000 \mathrm{m}\) at an average speed of \(4.00 \mathrm{m} / \mathrm{s} .\) She runs the first $500 \mathrm{m}\( at an average of \)4.20 \mathrm{m} / \mathrm{s} .$ (a) How much time does she have to run the last \(500 \mathrm{m} ?\) (b) What should be her average speed over the last \(500 \mathrm{m}\) in order to finish with an overall average speed of \(4.00 \mathrm{m} / \mathrm{s} ?\)

In the problems, please assume the free-fall acceleration $g=9.80 \mathrm{m} / \mathrm{s}^{2}$ unless a more precise value is given in the problem statement. Ignore air resistance. At 3: 00 P.M., a bank robber is spotted driving north on I-15 at milepost $126 .\( His speed is \)112.0 \mathrm{mi} / \mathrm{h}$. At 3: 37 P.M., he is spotted at milepost 185 doing 105.0 milh. During this time interval, what are the bank robber's displacement, average velocity, and average acceleration? (Assume a straight highway.)