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A jet aircraft is traveling at 230 m/s in horizontal flight. The engine takes in air at a rate of 96.7 kg/s and burns fuel at a rate of 3.96 kg/s. The exhaust gases are ejected at 482 m/s relative to the aircraft. Find the thrust of the jet engine. Answer in units of N.
A box rests on a frozen pond, which serves as a frictionless
horizontal surface. If a fisherman applies a horizontal force with magnitude 48.0 N to the box and produces an acceleration of magnitude 3.00 m/s2, what is the mass of the box?
1. An ideal Otto cycle has a compression ratio of 7. At the beginning of the compression
process, air is at 107 kPa and 19°C, and 750 kJ/kg of heat is transferred to air during
the constant-volume heat-addition process. Accounting for the variation of specific
heats of air with temperature, determine (a) the maximum temperature and pressure
that occur during the cycle, (b) the net work output, (c) the thermal efficiency, and
(d) the mean effective pressure for the cycle.
(e) Also, determine the power output from the cycle, in kW, for an engine speed
of 3700 rpm (rev/min). Assume that this cycle is operated on an engine that has four
cylinders with a total displacement volume of 1.9 L.
A neutron in a reactor makes an elastic headon collision with the nucleus of an atom initially at rest. Assume: The mass of the atomic nucleus is about 11.3 the mass of the neutron. What fraction of the neutron’s kinetic energy is transferred to the atomic nucleus?
2. At a sharp horizontal circular tum a train slows down going from 90.0 km/h to 50.0 km/h in
the 15.0 s it takes to round the bend. The radius of the curve is 150 m. Assume the train
continues to slow down at the same rate. At the moment the train speed reaches 50.0 km/h
calculate:
(a)the magnitude and direction of the tangential acceleration.
(b)the radial acceleration (magnitude and direction).
(c)the magnitude and direction of the total acceleration.
1. A person is jumping from a height ho= 10 m with zero initial velocity and a cricket ball is thrown directly upward with an initial velocity =9.8 m/s at the same instant when time t=0 s as shown in Fig. 1. Consider h=11.5m and i and to be the unit vectors along the X and Y axis. Gravity is acting along the direction and the magnitude of gravitational acceleration is given by g 9.81 m/s². The red dot on the person represents his center of mass.
(a)If the person and the cricket ball consist of a system, find the position and velocity of the center of mass of the system at time t = 0.5 s
(b)If it takes 0.01 seconds for the person to come to complete rest when he hits the ground, calculate the average force acting on the person.
(c)Now consider when the person hits the ground, he bends his knees such that the center of mass of his body is lowered by 15 cm. If the maximum force that the bone of his legs can withstand is 50000 N, will he break his legs?
If the person and the cricket ball consist of a system, find the position and velocity of the center of mass of the system at time t=0.5 s
Assume that a car weighing 1200kg is traveling east at a velocity of 12.0 m/s. Another car, 40 meters away, weighs 1800 kilograms and travels at a speed of 20.0 meters per second to the east. How do you determine the location of the system's center of mass when it consists of two cars? How do you calculate each car's momentum? What about the overall system's momentum?
You answered me in a previous question that, in a scenario in which two objects A&B are side by side, then a force is applied to B to accelerate B away from A, then the force is removed from B so that B travels away from A at a constant velocity, that time, in reality, will move slower in B than A.
I would like to ask a follow up question.
In the scenario, if the two objects return to rest in regard to one another, (at some distance apart from each other) either by a reverse force being applied to B until it slows to a stop in regard to A, or a force being applied to A accelerating it in the direction of B until it reaches the velocity of B, can we say that time will again pass at the same rate for A&B, but that less time will have passed in B than A? I.e., clocks that were synchronized prior to the initial force will again be synchronized but the clock in B will read behind the clock in A.
