Question

A rescue plane flying at $162km/hr$ drops a survival package from a height of $70m$ for the needy peoples. Find out where the package strikes the ground ?

• A. $85m$ behind the plane
• B. $170m$ behind the plane
• C. $255m$ behind the plane
• D. $462m$ behind the plane
• E. Directly beneath the plane

Answer 1

The correct option is B $170m$ behind the plane

The horizontal and vertical velocities of package are independent to each other. Let $t$ be the time taken by package to strike the ground , then by

$h=\frac{1}{2}g{t}^2$

$70=\frac{1}{2}\times 9.8t^2$

$t=3.78s$

now the horizontal distance travelled by package (the horizontal velocity of package will be equal to the velocity of plane)

$d=162km/hr\times 3.78s$

or $d=170m$ , behind the plane