VECTORS

the angles which a vector A = i+j+√2k makes with X Y Z axes respectively are
a) 60° 60° 60°
b) 45° 45° 45°
c) 60° 60° 45°
d) 45° 45° 60°

3 Answers

45
Raunaq Saha ·

C)60°,60° and 45°
angle with x-axis :
cosθ= A.B|A||B|=1√1+1+2=12
θ=60°
angle with y-axis :
cosθ= A.B|A||B|=1√1+1+2=12
θ=60°
angle with z-axis :
cosθ= A.B|A||B|=√2√1+1+2=1√2
θ=45°

59
Sohini Marik ·

there's an easier way...
A=√1+1+√2=2
Ax=1=2cosθx=>cosθx=1/2 =>θx=60°
Ay=1=2cosθy=>cosθy=1/2 =>θy=60°
Az=√2=2cosθz=>cosθz=1/√2 =>θz=45°

466
Himanshu Giria ·

45 45 & 60 °

Your Answer

Close [X]