A block is kept on the floor of an elevator at rest. The elevator starts descending with an acceleration of 12 m / s 2. The displacement (in cm ) of the block during the first 0.2 s after the elevator starts descending is (Take g=10 m / s 2 )

Question

A block is kept on the floor of an elevator at rest. The elevator starts descending with an acceleration of 12 m / s 2. The displacement (in cm ) of the block during the first 0.2 s after the elevator starts descending is (Take g=10 m / s 2 ) (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

The block will undergo free fall. ⇒ s =(1/2) g(0.2)2 =5 × 0.40=0.2 m

Q. A block is kept on the floor of an elevator at rest. The elevator starts descending with an acceleration of $12 m / s^{2}$ . The displacement (in $c m$ ) of the block during the first $0.2 s$ after the elevator starts descending is
(Take $g = 10 m / s^{2}$ )

The block will undergo free fall.
$\Rightarrow s = \frac{1}{2} g (0.2)^{2}$
$= 5 \times 0.40 = 0.2 m$

Q. A block is kept on the floor of an elevator at rest. The elevator starts descending with an acceleration of 12m/s2. The displacement (in cm ) of the block during the first 0.2s after the elevator starts descending is (Take g=10m/s2 )

The block will undergo free fall. ⇒s=21​g(0.2)2 =5×0.40=0.2m

Q. A block is kept on the floor of an elevator at rest. The elevator starts descending with an acceleration of $12 m / s^{2}$ . The displacement (in $c m$ ) of the block during the first $0.2 s$ after the elevator starts descending is
(Take $g = 10 m / s^{2}$ )

The block will undergo free fall.
$\Rightarrow s = \frac{1}{2} g (0.2)^{2}$
$= 5 \times 0.40 = 0.2 m$