Question

Two stones thrown at different angles have same initial velocity and same range. If H is the maximum height attained by one stone thrown at an angle of 30°, then the maximum height attained by the other stone is (b) H (c) 2H (d) 3H

Answer 1

Explanation :- case 1 :-when body moves upward direction.

initial velocity =u

final velocity =v=0

now, v=u+at  

Here, v=0,a=−g [acceleration is downward direction]

0=u−gt⇒t=u/g  

Maximum height = h

u  

2

=2gh⇒h=u  

2

/2g---(1)

Answer 2

Explanation:

Assuming the angle of projection is = π/3 radians:

2

π

−

3

π

=

6

π

radians

⇒ the angle of projection of the other object

let the maximum heights be: h

1

and h

2

:

h

2

h

1

=

sin

2

(

6

π

)

sin

2

(

3

π

)

h

2

h

1

=

(

2

1

)

2

(

2

3

)

2

h

2

h

1

=

(

4

1

)

(

4

3

)

=

1

3

h

2

=

3

h

1