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1 KINEMATICS P10 006 There are three observes, Chris, Pat, and Joe.
There are two aircraft, a Boeing 787 and an Airbus 320. Chris is onboard the
Boeing plane and Pat is flying in the Airbus. Joe is relaxing at the airport. All the following statements are incorrect.
Explain why each statement is wrong. Re-write each statement so that the
physics is correct. A The speed of the Boeing plane is 300 km.h-1. B
The speed of the Airbus plane is 400 km.h-1 due North. C
The velocity of the Boeing is 300 km.h-1. D The velocity of the Airbus plane is 400 km.h-1
due North. E
The speed of the Boeing plane is 300 km.h-1 due East with
respect to Joe. F The velocity of the Airbus is 400 km.h-1
with respect to Joe. G
With respect to Chris the speed of the Airbus is 400 km.h-1
and with respect to
Pat, the speed of the Boeing is 300 km.h-1. H
With respect to Joe, the speed of the Boeing is 300 km.h-1. I
With respect to Joe, the magnitude of the velocity of the Airbus is
-400 km.h-1. J
The displacement of the Boeing is 1.2 km. K
The distance of the Airbus is 2.5 km due North. L
The magnitude of the displacement of the Boeing with respect to Joe is
-1.2 km. M
The distance of the Airbus to the Boeing is 7.5 km due North. View solution below only after you have completed the answering
the question. |
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Solution A The speed of the Boeing plane is 300 km.h-1. Speed is a relative concept. The speed of the plane has to specified with respect to an observer. For example,
with respect to Joe, the speed of the Boeing is 300 km.h-1. B
The speed of the Airbus plane is 400 km.h-1 due North. Speed is a relative concept. The speed of the plane has to specified with respect to an observer. For example,
with respect to Joe, the speed of the Boeing is 300 km.h-1. Speed is a scalar quantity. Cannot have a direction associated with
speed. C
The velocity of the Boeing is 300 km.h-1. Velocity a relative concept. The velocity of the plane has to specified with respect to an observer. You need to
give the magnitude of the vector and its direction. For example, with respect
to Joe, the velocity of the Boeing is 300 km.h-1 due East. D The velocity of the Airbus plane is 400 km.h-1
due North. Velocity a relative concept. The velocity of the plane has to specified with respect to an observer. You need to
give the magnitude of the vector and its direction. For example, with respect
to Joe, the velocity of the Airbus is 400 km.h-1 due North. E
The speed of the Boeing plane is 300 km.h-1 due East with
respect to Joe. Speed is a scalar quantity. Cannt have a direction associated with
speed. For example, the speed of the Boeing with respect to Joe is 300
km.h-1. F The velocity of the Airbus is 400 km.h-1
with respect to Joe. You need to give the magnitude of the vector and its direction. For
example, with respect to Joe, the velocity of the Airbus is 400 km.h-1
due North G
With respect to Chris the speed of the Airbus is 400 km.h-1
and with respect to
Pat, the speed of the Boeing is 300 km.h-1. The relative speeds of the two observers must have the same value. Chris observes the Airbus moving at a speed of 250 km.h-1
and observes the Airbus flying due East. Pat observes the Boeing moving at a
speed of 250 km.h-1 and observes the plane flying due West. H
With respect to Joe, the speed of the Boeing is -300 km.h-1. Speed is a scalar quantity. The speed is never a negative
quantity. The speed of the Boeing is 300 km.h-1. I
With respect to Joe, the magnitude of the velocity of the Airbus is
-400 km.h-1. The magnitude of a Vector is never a negative quantity. The
magnitude of the velocity of the Airbus is 400 km.h-1. J
The displacement of the Boeing is 1.2 km. Displacement is a vector and must be specified with respect to an
Origin in terms of its magnitude and direction. For example, the displacement
of the Boeing is 1.2 km due North of Joe. K
The distance of the Airbus is 2.5 km due North. Distance is a scalar quantity. Cannot associate a direction with
distance. For example, the distance between the Boeing and Airbus is 2.5 km. L
The magnitude of the displacement of the Boeing with respect to Joe is
-1.2 km. The magnitude of a vector is never a negative quantity. With
respect to Joe, the magnitude of the displacement of the Boeing is 1.2 km. M
The distance of the Airbus to the Boeing is 7.5 km due North. Distance is a scalar quantity. Cannot associate a direction with
distance. The distance between the Boeing and Airbus is 7.5 km. |
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