A train 450 m long is moving on a straight track with a speed of 83.9 km/h. The engineer applies the brakes at a crossing, and later the last car passes the crossing with a speed of 17.1 km/h. Assuming constant acceleration, determine how long the train blocked the crossing. Disregard the width of the crossing

Q: A person takes a trip, driving with a constant speed of 95.5 km/h, except for a 24.0-min rest stop.…

A: (a) Expression for total time travelled

Q: Car A is traveling at a location where the speed limit is 100 km/h. The police officer in car P…

A: velocity of car A at point P = 136 km/hr velocity of car A after 4.6 sec = 100 km/hr initial…

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A: speed of electrical signals along nerve cells (v) = 34 m/s distance travelled by signal resulting…

Q: A subway train starts from rest at a station and accelerates at a rate of 2.50 m/s? for 15.90…

A:

Q: (a) What is the magnitude of the average acceleration of a skier who, starting from rest, reaches a…

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A: We know that:

Q: A jetliner, traveling northward, is landing with a speed of 72.1 m/s. Once the jet touches down, it…

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A: Given: acceleration of automobile aa=2.3 m/s2 constant speed of truck ut=vt=9.6 m/s

Q: Car A is traveling at a location where the speed limit is 100 km/h. The police officer in car P…

A:

Q: This is a practice problem that I'm pretty sure I got correct. I got that she rode 3388 meters on…

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Q: At the moment of departure of a train, the signalman is standing next to the first wagon, which…

A: Answer            63.6 Sec

Q: A person takes a trip, driving with a constant speed of 93.0 km/h except for a 22.0-min rest stop.…

A:

Q: Dr. John Paul Stapp was a U.S. Air Force officer who studied the effects of extreme acceleration on…

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Q: A train 400 m long is moving on a straight track with a speed of 82.4 km/h. The engineer applies the…

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A:

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A: Initial speed of the car is V = 70.4 km/h  Reaction time is t = 0.520 s

Q: Car A is traveling at a location where the speed limit is 100 km/h. The police officer in car P…

A:

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Q: Car A is traveling at a location where the speed limit is 100 km/h. The police officer in car P…

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Q: An athlete swims the length of a 41.0-m pool in 15.0 s and makes the return trip to the starting…

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Q: Car A is traveling at a location where the speed limit is 100 km/h. The police officer in car P…

A: Equation of motion are given by: v=u+ats=ut+12at2v2-u2=2as Here u is initial velocity, v is final…

Q: Car A is traveling at a location where the speed limit is 100 km/h. The police officer in car P…

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Q: Chapter 4- questn-30 The velocity of a particle moving in the xy plane is defined by i = (6.0t –…

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Q: A jetliner, traveling northward, is landing with a speed of 57.5 m/s. Once the jet touches down, it…

A:

Q: Car A is traveling at a location where the speed limit is 100 km/h. The police officer in car P…

A:

Q: car was traveling at 33.0 m/s on a poorly lit country road.  The driver started to brake 0.35…

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Q: Car A is traveling at a location where the speed limit is 100 km/h. The police officer in car P…

A: Given two car A and car P traveling at a location speed of car A is 100km/h and driver of car A is…

Q: In a test run, a certain car accelerates uniformly from zero to 21.6 m/s in 2.15 s. (a) What is the…

A: Given Data: Initial velocity of car (u) = 0 m/s Final velocity of car (v) = 21.6 m/s time (t) = 2.15…

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Q: (a) What is the magnitude of the average acceleration of a skier who, starting from rest, reaches a…

A:

Relative Velocity

It is a measurement of an object with regards to the other object which is moving or stable or stationary. For example, if we are traveling in a bus and the bus is moving at speed of 50km/hr, then our speed is according to the nearby passenger on the bus is zero. According to them, we are not moving. But if one person standing on the ground or road observes us from outside of the bus, according to him we are moving at a speed of 50km/hr and the bus is also moving at a speed of 50km/hr. Now, the motion is recognized by the observer, it depends on a frame of reference or observer. This is motion called relative motion.