If the resultant of three forces `vec(F)_(1)=phat(i)+3hat(j)-hat(k),vec(F)_(2)=-5hat(i)+hat(j)+2hat(k)` and `vec(F)_(3)=6hat(i)-hat(k)` acting on a pa
If the resultant of three forces `vec(F)_(1)=phat(i)+3hat(j)-hat(k),vec(F)_(2)=-5hat(i)+hat(j)+2hat(k)` and `vec(F)_(3)=6hat(i)-hat(k)` acting on a particle has magnitude equal to 5 units, then the value (s) of p is (are)
A. `-6`
B. `-4`
C. 2
D. 4
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Correct Answer - B::C::D
`R=(u^(2)sin2theta)/(g)`
`480 = (70^(2)sin2theta)/(9.8) " "48=(4900)/(98)sin2theta`
`(24)/(25)=sin2theta`
`(24)/(25) = 2 sin theta cos theta`
`sintheta=(4)/(5)" or "sintheta_(2)=(3)/(5)`
Maximum height = `(u^(2)sin^(2)theta)/(2g)`
Ratio of maximum height = `sin^(2)theta_(2),sin^(2)thetat=9.16`
Minimum speed = `v cos theta`
Ratio of minimum speed `=costheta_(2) : costheta_(1) = 4 : 3`
`theta_(1)+theta_(2)= 90^(@)`
`therefore " "(theta_(1)+theta_(2))/(2)=45^(@)`
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