A projectile can have the same range R for two angles of projection. If `t_(1)` and `t_(2)` be the times of flight in the two cases:-

Options

A. `1/R`
B. `R`
C. `R^2`
D. `1/R^2`

Answer

B

Explanation

Range is same for angles of projection ` theta and (90^@ - theta)`
`:. t_(1)=(2usin theta)/(g) and t_2 =(2usin (90^@- theta))/g`
`:. t_1t_2=(4u^2sin thetacos theta)/(g^2)=2/gxx((u^2sin2theta)/g)=(2R)/g`
`:. t_1t_2` is proportional to R.