KinematicsMedium
Question
A body has an initial velocity of 3 ms-1 and has a constant acceleration of 1 ms-2 normal to the direction of the initial velocity. Then its velocity, 4 second after the start is
Options
A.7 ms-1 along the direction of initial velocity
B.7 ms-1 along the normal to the direction of the initial velocity
C.7 ms-1 mid-way between the two directions
D.5 ms–1 at an angle of tan-1 4/5 with the direction of the initial velocity
Solution
u = 3m/s î a = 1ĵ m/s2
a is ⊥ u
so V after 4 sec
V = u + at
V = 3î + 1ĵ × 4

V = 3î + 4ĵ

= 5 m/s
and tan θ =
θ = tan-1
with the direction of the initial velocity.
a is ⊥ u
so V after 4 sec
V = u + at
V = 3î + 1ĵ × 4

V = 3î + 4ĵ
and tan θ =
θ = tan-1
Create a free account to view solution
View Solution FreeMore Kinematics Questions
The coordinate of a particle moving in a plane are given by x (t) = a cos ( pt) and y (t) = bsin ( pt) , where a, b (...A particle moving along a straight line with uniform acceleration has velocities 7m /s at A and 17 m/s at C. B is the mi...A particle is thrown upwards from ground. It experiences resistance force which can produce retardation 2 m/s2. The rati...A particle is projected from surface of the inclined plane with speed u and at an angle q with the horizontal. After som...A river of width 200 m is flowing from west to east with a speed of $18\text{ }km/h$. A boat, moving with speed of $36\t...