Kinematics Question 458
Assertion: The maximum horizontal range of projectile is proportional to square of velocity. Reason: The maximum horizontal range of projectile is not equal to maximum height attained by projectile.
Options:
A) If both assertion and reason are true and the reason is the correct explanation of the assertion.
B) If both assertion and reason are true but reason is not the correct explanation of the assertion.
C) If assertion is true but reason is false.
D) If the assertion and reason are both false.
E) If assertion is false but reason is true.
Show Answer
Answer:
Correct Answer: C
Solution:
$ R=\frac{u^{2}\sin 2\theta }{g} $ $ {R _{\max }}=\frac{u^{2}}{g} $ when $ \theta =45{}^\circ $ $ {R _{\max }}\propto u^{2} $
Height $ H=\frac{u^{2}{{\sin }^{2}}\theta }{2g} $
therefore $ {H _{\max }}=\frac{u^{2}}{2g} $
when $ \theta =90{}^\circ $
It’s clear that $ {H _{\max }}=\frac{{R _{\max }}}{2} $
BETA
