MCQ
An object is projected from ground with speed $20 \,m / s$ at angle $30^{\circ}$ with horizontal. Its centripetal acceleration one second after the projection is .......... $m / s ^2$ [Take $g=10 \,m / s ^2$ ]
- ✓$10$
- B$0$
- C$5$
- D$12$
✓
Answer
Correct option: A.
$10$
a
(a)
(a)
$T =\frac{2u \sin \theta}{g}$
$=\frac{2 \times 20 \times 1 / 2}{10}=2 \sec$
$t=1$ partical at highest point
$a_c=g=10 m / s ^2$
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