A healthy man standing at a distance of 7m from a 11.8m tall building sees a kid slipping from the top floor. With what speed (assumed uniform) should he run to catch the kid at the arms lenght (1.8 m) ?

Open in App

Solution

Here,
h = 11.8 m
g = 10 ms^-2
Arms height = 1.8 m
So the height at which the man must catch the child = 11.8 – 1.8
= 10 m
Now time taken for the boy to reach down
t = √(2h/g)
=> t = √(2×10/10)
=> t = √2 s
Now the man must travel 7 m in √2 s
Thus his velocity = 7/√2
≈ 5 ms^-1

Suggest Corrections

Similar questions

A healthy youngman standing at a distance of 7 m from 11.8 m high building sees a kid slipping from the top floor. With what speed (assumed uniform) should he run to catch the kid at the arms height (1.8)m ?

Q. A man standing at a distance of 6m from a building 21.3 m high observes a kid slipping from the top floor. With what speed should he run to catch the kid at a height of 2 m from the ground? (Assume speed of the person to be uniform;

g = 10 m s^{- 2}

A 1.8 m tall man is standing at some distance from a 31.8 m tall building. The angle of elevation from his eyes to the top of the building increases from $30^{\circ}$ to $60^{\circ}$ as he walks towards the building. Find the distance he walked towards the building.

Join BYJU'S Learning Program

A healthy man standing at a distance of 7m from a 11.8m tall building sees a kid slipping from the top floor. With what speed (assumed uniform) should he run to catch the kid at the arms lenght (1.8 m) ?

Here,h = 11.8 mg = 10 ms-2Arms height = 1.8 mSo the height at which the man must catch the child = 11.8 – 1.8 = 10 mNow time taken for the boy to reach downt = √(2h/g)=> t = √(2×10/10)=> t = √2 sNow the man must travel 7 m in √2 sThus his velocity = 7/√2 ≈ 5 ms-1

Here,
h = 11.8 m
g = 10 ms^-2
Arms height = 1.8 m
So the height at which the man must catch the child = 11.8 – 1.8
= 10 m
Now time taken for the boy to reach down
t = √(2h/g)
=> t = √(2×10/10)
=> t = √2 s
Now the man must travel 7 m in √2 s
Thus his velocity = 7/√2
≈ 5 ms^-1