Question

When Rahul walks up a stationary escalator, then

he takes 20 s to reach the top. While when he

walks up a moving escalator, he takes 10 s to reach

the top. The time taken by him to reach the top when

stand still on the moving escalator is​

Answer 1

Explanation:

As the escalator is stationary, so the distance covered in t

1

seconds is L which is the length of the escalator.

Speed of man w.r.t. the escalator, v

me

=

t

1

L

b.When the man is stationary, by taking man as a reference point the distance covered by escalator is L in time t

2

.

Speed of escalator, v

c

=

t

2

L

c. Speed of man w.r.t. the ground, v

m

=v

me

+v

c

_

⇒v

m

=

t

1

L

+

t

2

L

=L[

t

1

1

+

t

1

1

]= L[

t

1

t

2

t

1

+t

2

]

∴t=

v

m

L

=[

t

1

+t

2

t

1

t

2

]

which is the time taken by the man to walk up the moving escalator.

Answer 2

Answer:

30s

Explanation: