Sound waves travel at 350 ms-1 through warm air and at 3500 ms-1 through brass. The wavelength of a 700 Hz acoustic wave as it enters brass from warm air
ADecrease by a factor 10.
BIncrease by a factor 20.
CIncrease by a factor 10.
DDecrease by a factor 20.
Preeti looked at the night sky of 13th August and observed a Full Moon. What shape of Moon will she
most probably observe on 26th August?
This should be a crescent (C) because it's only 13 days after full moon, not 14.
The dress shown in the picture is known as _________ and is traditional dress of __________.
A Kimono, Australia
B Hanbok, Japan
C Kalli Mundu, India
D None of these
The given figure shows phases of
the Moon as seen from the Earth
surface (as shown with arrow
point). The following statements
describe the lunar cycle. Select
the correct statement(s).
(1) The lunar phases progress from Full Moon, Crescent Moon, First Quarter Moon, Gibbous Moon and New Moon, before returning through Gibbous Moon, last Quarter Moon, Crescent Moon and Full Moon.
(2) From phase 1 to 3 waxing crescent is seen and from phase 7 to 9 waning crescent is seen.
(3) From phase 3 to 5 waxing gibbous is seen and from phase 5 to 7 waning gibbous is seen.
(4) 50% illuminated Moon is seen in phase '3' as well as in phase '7'.
A 1 only
B 1 and 3
C 1, 2 and 4
D 2, 3 and 4
d is the answer
Mr. Shivam hangs two soft drink
cans on each end of a balance and
keeps them hanging till they get
evenly balanced. He then gently
pulls the tab open on one can
until he hears a whoosh sound. He
then lets the cans hang in balance.
After thirty minutes he observes
that the balance has got disturbed.
Pupils of Mr. Shivam try to explain
this as given.
Who among the pupils is/are INCORRECT?
A Yogesh and Arun
B Rohit only
C Rohit and Viraj
D Arun only
A body of mass m1 moving with a uniform velocity v collides with another body of mass m2 at rest and then the two together begin to move with a velocity
A9 : 1
B12 : 1
C16 : 1