A block is kept on a frictionless inclined surface with angle of inclination α. The incline is given an acceleration a to keep the block stationary. Then a is equal to
g/tanα
g cosecα
g
g
D.
g
A ball is thrown from a point with a speed ν0 at an angle of projection θ. From the same point and at the same instant person starts running with a constant speed ν0/2 to catch the ball. Will the person be able to catch the ball? If yes, what should be the angle of projection?
yes, 60°
yes, 30°
no
no
A.
yes, 60°
Man will catch the ball if the horizontal component of velocity becomes equal to the constant speed of man i.e.
All the graphs below are intended to represent the same motion. One of them does it incorrectly. Pick it up.
C.
A particle moves in a straight line with retardation proportional to its displacement. Its loss of kinetic energy for any displacement x is proportional to
x2
ex
x
x
A.
x2
In this problem acceleration (a) is given in terms of displacement (x) to determine the velocity with respect to position or displacement we have to apply integration method.
From given information a =-kx, where a is acceleration, x is displacement and k is proportionality constant.
Let for any displacement from 0 to x , the velocity changes from vo to v