Buoyancy from water. Buoyancy is an upward force on an object immersed in a fluid (i.e., a liquid or a gas), enabling it to float or at least to appear lighter.
Answer:9.75 m/s
Explanation:
Given
Length of ladder 
Foot the ladder is moving away with speed of 
From diagram
------1
at 


Now differentiating equation 1 w.r.t time




negative indicates distance is decreasing with time
Question four bulbs A,B,C and D are connected in a circuit shown in the figure below, the letters X, Y and Z represent three switches. Which switch is used to operate switch A separately?
Answer: x
Answer:
The cork moves up and down.
Explanation:
The cork moves up and down because of the waves produce due to tapping the surface of water. The cork experience movement due to placed on the water surface so when the wave passes through the medium by tapping of water, movement of cork also occur. Cork has high volume and lower mass so it floats on the water surface and experience movement due to waves.
"<span>a layer in the earth's stratosphere at an altitude of about 6.2
miles (10 km) containing a high concentration of ozone, which absorbs
most of the ultraviolet radiation reaching the earth from the sun."
Hope this helps!
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