Explanation:
According to the first law of limiting friction,
$\text{f}=\mu\text{N}$
where f is the frictional force
N is the normal reaction force
$\mu$ is the coefficient of static friction
and
$\text{N = mg}-\text{F}\cos\theta$
where m is the mass of the body
F is the contact force acting on the body
If we decrease the angle between this contact force and the vertical, then $\text{F}\cos\theta$ increases and the normal reaction force (N) as well as the frictional force (f) decrease.
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(a) Huygen wave theory |
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(c) Maxwell electromagnetic theory |
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(a) + 18.75 cm and convex lens |
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(c) + 20.25 cm and convex lens |
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