The range of a projectile fired at angle of `15^(@)` is 40m . If it is fired with the same speed at an angle of `45^(@)` then, which one of the following statement is an incorrect statement ?

Options

A. Final range is twice the initial range.
B. Final range is half of the initial range.
C. Final range is greater then the initial range
D. Final range is 80 m

Answer

B

Explanation

`R = (u^(2) sin 2 theta)/(2)`
`R prop sin 2theta`
`(R')/(R) = (sin 2 (45))/(sin 2 (15)) = (sin 90)/(sin 30) = 2`
(a) R' = 2R
(b) `R' = 2xx 40 = 80 m `
(c) `R ' gt R`
`:.` Option (b) is incorrect statement