A very broad elevator is going up vertically with a constant acceleration of $2\,m / s ^2$. At the instant when its velocity is $4\,m / s$ a ball is projected from the floor of the lift with a speed of $4\,m / s$ relative to the floor at an elevation of $30^{\circ}$. The time taken by the ball to return the floor is $..............\,s$ $\left(g=10\,m / s ^2\right)$
$\frac{1}{2}$
$\frac{1}{3}$
$\frac{1}{4}$
$1$
A projectile is thrown with a velocity of $50\,\, ms^{^{-1}}$ at an angle of $53^o$ with the horizontal .Choose the incorrect statement
Which one of the following statements is not true about the motion of a projectile?
A body is projected at an angle $\theta $ with horizontal, another body is projected with the same speed at an angle $\theta $ with the vertical then the ratio of the maximum height is
A cart is moving horizontally along a straight line with a constant speed of $30\,m / s$. A projectile is to be fired from the moving cart in such a way that it will retum to the cart (at the same point on cart) after the cart has moved $80\,m$. At what velocity (relative to the cart) must be projectile be fired? (Take $=10\,m / s ^2$ )
The maximum horizontal range of a projectile is $160\, m$. When the projectile is thrown with the same speed at an elevation of $30^o$ from the horizontal, it will reach to the maximum height of ......... $m$