Question

) A boy wants to jump from building A to building B. Height
of building A is 25 m and that of building B is 5m. Distance
between buildings is 4m. Assume that the boy jumps
horizontally, then calculate minimum velocity with which hehas to jump to land safety on building B.
25 m
B
5 m
4 ni
(a) 6 m/s (b) 8 m/s (c) 4 m/s (u) 2 m/s
​

Answer 1

Answer:

2m/s

Explanation:

A boy wants to jump from building A to building B. Height

of building A is 25 m and that of building B is 5m. Distance

between buildings is 4m. Assume that the boy jumps

horizontally, then calculate minimum velocity with which hehas to jump to land safety on building B

Vertical Distance between Buildings = 25 - 5 = 20 m

Horizontal Distance = 4 m

Let Say Boy jump with Velocity = V

Horizontal Velocity = V m/s

Vertical Velocity = 0

Time to Cover 20 m Vertical Distance  using S = ut + (1/2)at²

S = 20 m  u = 0  a = g  10 m/s²

20 = (1/2)(10)t²

=> t² = 4

=> t = 2

Horizontal Distance Covered = Vt  = 2V  

2V ≥ 4

=> V ≥ 2

minimum velocity with which he has to jump to land safety on building B = 2m/s

Answer 2

Answer:

2m/s

Explanation:

Vertical distance:25-5=20m

S=ut+1/2gt²

S=20,u=0,g=10m/s

Apply the values in given equation

20=0(t)+1/2(10)t²

20=5t²

20/5=t²

4=t²

t=√4=2s

horizontal distance=VT=2V

2V=4

V=4/2=2m/s

I hope this answer helps u

All the best