Find wrong statement - Vidyadip

MCQ

Find wrong statement

A
A car moving over a convex bridge is lighter than the same car resting on the same bridge
✓
A car moving over a convex bridge is heavier than the same car resting on the same bridge
C
A car moving over a concave bridge is heavier than the same car resting on the same bridge
D
The weight of the car changes due to the centrifugal force for above cases

✓

Answer

Correct option: B.

A car moving over a convex bridge is heavier than the same car resting on the same bridge

b
For convex bridge

$\mathrm{Mg}-\mathrm{N}=\frac{\mathrm{mv}^{2}}{\mathrm{R}}$

$\mathrm{N}=\mathrm{mg}-\frac{\mathrm{mv}^{2}}{\mathrm{R}}$

$\mathrm{N}<\mathrm{mg}$

For concave bridge

$\mathrm{N}-\mathrm{mg}=\frac{\mathrm{mv}^{2}}{\mathrm{R}}$

$\mathrm{N}=\mathrm{mg}+\frac{\mathrm{mv}^{2}}{\mathrm{R}}$

$N>m g$

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