JEE Mains 2020 Model Paper 4 New Pattern

Horizontal and vertical components of initial velocity are:
ux = 20√2cos45° = 20 m/s
and uy = 20√2sin45° = 20 m/s
After 1 s horizontal component remains unchanged while the vertical component becomes
vy = uy−gt = 20 - (10) (1) = 10 m/s
Due to explosion one part comes to rest. Hence, from conservation of linear momentum vertical component of second part will become vy′ = 20 m/s. Therefore, maximum height attained by the second part will be
H = h1+h2
Here, h1 = height attained in 1 s
= (20) (1) -

1

2

(10)(1)2
and h2 = height attained after 1 s =

v′y2

2g

=

(20)2

2×10

= 20 m
∴ H = 20 + 15 = 35 m