A particle is moving eastwards with velocity of $5\,m/s$. In $10 \,sec$ the velocity changes to $5 \,m/s$ northwards. The average acceleration in this time is
Zero
$\frac{1}{{\sqrt 2 }}\,\,m{\rm{/}}{s^{\rm{2}}}$ toward north-west
$\frac{1}{{\sqrt 2 }}\,\,m{\rm{/}}{s^{\rm{2}}}$ toward north-east
$\frac{1}{2}\,\,m{\rm{/}}{s^{\rm{2}}}$toward north-west
Two cars of masses $m_1$ & $m_2$ are moving along the circular paths of radius $r_1$ & $r_2$ respectively. Their speeds are such that they complete one round in same time. The ratio of angular speeds of two cars is
A particle is projected with a velocity $v$ such that its range on the horizontal plane is twice the greatest height attained by it. The range of the projectile is (where $g$ is acceleration due to gravity)
A ball is rolled off the edge of a horizontal table at a speed of $4\, m/s$. It hits the ground after $0.4\, sec$. Which statement given below is true?
A body of mass $m\, kg$ is rotating in a vertical circle at the end of a string of length $r$ metre. The difference in the kinetic energy at the top and the bottom of the circle is
The vector sum of two forces is perpendicular to their vector differences. In that case, the forces