A <math> <mn>60</mn> <mi mathvariant="normal">H</mi> <mi mathvariant="normal">P</mi> </math> <math></math> electric motor lifts an elevator having a maximum total load capacity of <math><mtext></mtext></math> <math> <mn>2000</mn> <mtext> </mtext> <mi mathvariant="normal">k</mi> <mi mathvariant="normal">g</mi> </math> . If the frictional force on the elevator is <math> <mn>4000</mn> <mtext> </mtext> <mi mathvariant="normal">N</mi> </math> <math><mtext></mtext></math> , the speed of the elevator at full load is close to: <math> <mfenced separators="|"> <mrow> <mrow> <mn>1</mn> <mi mathvariant="normal">H</mi> <mi mathvariant="normal">P</mi> <mo>=</mo> <mn>746</mn> <mtext> </mtext> <mi mathvariant="normal">W</mi> <mo>,</mo> <mtext> </mtext> <mi mathvariant="normal">g</mi> <mo>=</mo> <mn>10</mn> <msup> <mrow> <mrow> <mtext> </mtext> <mi mathvariant="normal">m</mi> <mi mathvariant="normal">s</mi> </mrow> </mrow> <mrow> <mrow> <mo>-</mo> <mn>2</mn> </mrow> </mrow> </msup> </mrow> </mrow> </mfenced> </math> <math><mfenced separators="|"><mrow><mrow><mtext></mtext><mtext></mtext><msup><mrow><mrow><mtext></mtext></mrow></mrow><mrow><mrow></mrow></mrow></msup></mrow></mrow></mfenced></math>

E ? = 9 s i n ? 1.6 × 10 3 x + 48 × 10 10 t k ˆ ? / m 4000 × V + m g × V = P 60 × 746 2000 × 4000 = V V = 1.86 m / s ≈ 1.9 m / s

A <math> <mn>60</mn> <mi mathvariant="normal">H</mi> <mi mathvariant="normal">P</mi> </math> <math></math>&nbsp;electric motor lifts an elevator having a maximum total load capacity of&nbsp;<math><mtext></mtext></math> <math> <mn>2000</mn> <mtext> </mtext> <mi mathvariant="normal">k</mi> <mi mathvariant="normal">g</mi> </math> . If the frictional force on the elevator is <math> <mn>4000</mn> <mtext> </mtext> <mi mathvariant="normal">N</mi> </math> <math><mtext></mtext></math>&nbsp;, the speed of the elevator at full load is close to: <math> <mfenced separators="|"> <mrow> <mrow> <mn>1</mn> <mi mathvariant="normal">H</mi> <mi mathvariant="normal">P</mi> <mo>=</mo> <mn>746</mn> <mtext> </mtext> <mi mathvariant="normal">W</mi> <mo>,</mo> <mtext> </mtext> <mi mathvariant="normal">g</mi> <mo>=</mo> <mn>10</mn> <msup> <mrow> <mrow> <mtext> </mtext> <mi mathvariant="normal">m</mi> <mi mathvariant="normal">s</mi> </mrow> </mrow> <mrow> <mrow> <mo>-</mo> <mn>2</mn> </mrow> </mrow> </msup> </mrow> </mrow> </mfenced> </math> <math><mfenced separators="|"><mrow><mrow><mtext></mtext><mtext></mtext><msup><mrow><mrow><mtext></mtext></mrow></mrow><mrow><mrow></mrow></mrow></msup></mrow></mrow></mfenced></math>

Ask & Answer Question

Option 1 -

$1.5 {m s}^{- 1}$

Option 2 -

$2.0 {m s}^{- 1}$

Option 3 -

$1.7 m / s^{- 1}$

Option 4 -

$1.9 m / s^{- 1}$

3 Views | Posted a month ago

Answered by

Vishal Baghel | Contributor-Level 10

a month ago

Correct Option - 4

Detailed Solution:

$\overset{?}{E} = (9 s i n ? (1.6 \times 10^{3} x + 48 \times 10^{10} t) \hat{k} ? / m)$

$4000 \times V + m g \times V = P$

$\begin{array}{r} \frac{60 \times 746}{2000 \times 4000} = V \\ V = 1.86 m / s \approx 1.9 m / s \end{array}$

Get authentic answers from experts, students and alumni that you won't find anywhere else

On Shiksha, get access to