An egg is thrown horizontally off a roof, which is 60 meters high, with an initial velocity of 6.5 m/s. How long does it take to hit the ground, and how far does it go in the x direction?

2 Answers
Aug 11, 2018

It will take 3.5s3.5s to reach the ground.

It will go 22.75m22.75m in the horizontal direction.

Explanation:

The egg will come down because of gravity but due to its imparted horizontal velocity,it will move forward from the bottom of the roof!

So,if it takes time tt to reach the ground,considering vertical motion,we can use h=1/2 at^2h=12at2 where, hh is the height a=ga=g i.e acceleration due to gravity.

Given, h=60mh=60m and taking g=9.81 ms^-2g=9.81ms2 we get,

t=sqrt((2h)/g)=sqrt((2×60)/9.81)=3.5st=2hg=2×609.81=3.5s

So,in this time if it moves a distance of xx in the horizontal direction due to constant velocity v=6.5 ms^-1v=6.5ms1

Then,we find x=vt=6.5×3.5=22.75mx=vt=6.5×3.5=22.75m

Aug 11, 2018

Egg is thrown with horizontal velocity. Therefore, initial vertical velocity of egg =0=0. Time taken by egg to fall down under gravity and hit the ground can be found by the kinematic expression

h=ut+1/2g t^2h=ut+12gt2

Inserting given vales we get

60=0xxt+1/2(9.81) t^260=0×t+12(9.81)t2
=> t=sqrt((60xx2)/9.81)t=60×29.81
=> t=3.5\ s

Distance traveled in x direction=v_ht=6.5xx3.5=22.7\ m