The moment of inertia of a rectangular section 3 cm wide and 4 cm deep about X-X axis is
A. 9 cm4
B. 12 cm4
C. 16 cm4
D. 20 cm4
Answer: Option C
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The resultant of two equal forces P making an angle $$\theta ,$$ is given by
A. $$2{\text{P}}\sin \frac{\theta }{2}$$
B. $$2{\text{P}}\cos \frac{\theta }{2}$$
C. $$2{\text{P}}\tan \frac{\theta }{2}$$
D. $$2{\text{P}}\cot \frac{\theta }{2}$$
A. Equal to
B. Less than
C. Greater than
D. None of these
If a number of forces are acting at a point, their resultant is given by
A. $${\left( {\sum {\text{V}} } \right)^2} + {\left( {\sum {\text{H}} } \right)^2}$$
B. $$\sqrt {{{\left( {\sum {\text{V}} } \right)}^2} + {{\left( {\sum {\text{H}} } \right)}^2}} $$
C. $${\left( {\sum {\text{V}} } \right)^2} + {\left( {\sum {\text{H}} } \right)^2} + 2\left( {\sum {\text{V}} } \right)\left( {\sum {\text{H}} } \right)$$
D. $$\sqrt {{{\left( {\sum {\text{V}} } \right)}^2} + {{\left( {\sum {\text{H}} } \right)}^2} + 2\left( {\sum {\text{V}} } \right)\left( {\sum {\text{H}} } \right)} $$
A. $${\text{a}} = \frac{\alpha }{{\text{r}}}$$
B. $${\text{a}} = \alpha {\text{r}}$$
C. $${\text{a}} = \frac{{\text{r}}}{\alpha }$$
D. None of these
Ix = bh³/12 ,so
Ix = 3x4³/12
Ix= 16cm⁴
Bd^3/12= 3*64/12= 16
Moments of inertia of rectangular section about X-X axis
=bh^3/12
=3×4^3 /12
= 16cm
I = BD3/12 : 3*64/12 = 16.
BD^3/12 use this
I think the formula is Ixx=Iyy=bd^3/12
If three forces actiing in a different planes can be represented by a triangle, these Will be in
Exaplain
Can you please explain