Answer:
a. Wavelength = λ = 20 cm
b. Next distance of maximum intensity will be 40 cm
Explanation:
a. The distance between the two speakers is 20cm. SInce the intensity is maximum which refers that we have constructive interference and the phase difference must be an even multiple of π and equivalent path difference is nλ.
Now when distance increases upto 30 cm between the speakers, the sound intensity becomes zero which means that there is destructive interference and equivalent path is now increased from nλ to nλ + λ/2.
This we get the equation:
(nλ + λ/2) - nλ = 30-20
λ/2 = 10
λ = 20 cm
b. at what distance, sound intensity will be maximum again.
For next point calculation for maximum sound intensity, the path difference must be increased (n+1) λ. The distance must increase by λ/2 from the point of zero intensity.
= 30 + λ/2
= 30 + 20/2
=30+10
=40 cm
Answer:
The lever is a movable bar that pivots on a fulcrum attached to a fixed point. The lever operates by applying forces at different distances from the fulcrum, or a pivot. As the lever rotates around the fulcrum, points farther from this pivot move faster than points closer to the pivot.
IF HELPED MARK AS BRAINLIEST
Answer: The correct option is option E (the Sun is seen blocking different constellations in the course of a year.
Explanation:
The earth, which is one of the planets of the solar system that supports life, is shperical in shape. The spherical ( round) shape of the earth is marked by the intervening highlands and oceans on its surface.
Evidence to show that the earth is shperical are:
--> The Lunar eclipse: During an eclipse of the Moon, the shadow of the Earth is always seen to be round.
--> Ships Visibility: When ships travel a large distance away, we see their hulls disappear first and their masts disappear last.
-->Altitude of Polaris (North Star): The height of the North Star changes as we travel to different latitudes. That is ,increases as you move toward the North pole, or decreases as you move toward the equator.
--> Aerial photographs: Photographs of the Earth from space always show a round body.
The statement that doesn't prove that the earth is spherical in shape is (the Sun is seen blocking different constellations in the course of a year). The sun is seen in front of stars blocking different constellation in a year because the earth orbits round the sun in a year and not that it is shperical in shape.
Answer:
a.18.5 m/s
b.1.98 s
Explanation:
We are given that
a.Let 
be the initial velocity of the ball.
Distance,x=30 m
Height,h=1.8 m
Substitute the values
Initial velocity of the ball=18.5 m/s
b.Substitute the value then we get
t=1.98 s
Hence, the time for the ball to reach the target=1.98 s
Answer:
t'=1.1897 μs
Explanation:
First we will calculate the velocity of micrometeorite relative to spaceship.
Formula:
where:
v is the velocity of spaceship relative to certain frame of reference = -0.82c (Negative sign is due to antiparallel track).
u is the velocity of micrometeorite relative to same frame of reference as spaceship = .82c (Negative sign is due to antiparallel track)
u' is the relative velocity of micrometeorite with respect to spaceship.
In order to find u' , we can rewrite the above expression as:
u'=0.9806c
Time for micrometeorite to pass spaceship can be calculated as:
(c = 3*10^8 m/s)
t'=1.1897 μs
