In the figure below, a horizontally moving block can take three frictionless rou
ID: 1284053 • Letter: I
Question
In the figure below, a horizontally moving block can take three frictionless routes, differing only in elevation, to reach the dashed finish line.
(a) Rank the routes according to the speed of the block at the finish line, greatest first (use the notation > or =, for example 2=3>1).
(b) Rank the routes according to the travel time of the block to the finish line, greatest first (use the notation > or =, for example 2=3>1).
In the figure below, a horizontally moving block can take three frictionless routes, differing only in elevation, to reach the dashed finish line. (a) Rank the routes according to the speed of the block at the finish line, greatest first (use the notation > or =, for example 2=3 >1). (b) Rank the routes according to the travel time of the block to the finish line, greatest first (use the notation > or =, for example 2=3 >1).Explanation / Answer
CONSIDERING ROUTE 2 AS REFERNCE
ACCORDING TO CONSERVATION OF ENERGY:
ROUTE 1 IS HIGHER THAN THE LEVEL GROUND .
SO, INIITIAL KINETIC ENERGY =(1/2) MV2
FINAL ENRGY =(1/2)MVf2 + mgh
on eqauting : (energy conservation )
(1/2)MV12 =1/2) MV22 - mgh
final K.E (HENCE SPEED ) LOWER THAN (2) ROUTE
IN THE SAME WAY.. FOR ROUTE (3)
INIITIAL ENERGY =(1/2) MV22 +MGH
FINAL ENRGY =(1/2)MV32
(3) ROUTE HAS HIGHEr KINETIC ENERGY.
SO SPEED = 3 > 2> 1
(b) TIME TAKEN ; TIME IS INVERSELY PROPERTIONAL TO SPEED
THEREFORE
FOR TIME = 1> 2>3