Solid and liquids are much more denser than gas because their molecules are close to each other and with that the molecules of them can't move that freely unlike the gas molecules. Also, because of being near to each other the molecules of solid and liquids became heavy making them dense.
light waves. the other waves like gamma rays or infrared waves or radio waves are all not visible to the eye. light is the only thing out of those you can see.
Explanation:
Work cannot be increased by using a machine of some kind.
Answer:
Pressure applied by the man= 285103.125 
or 41.35 
Explanation:
Pressure is defined as the perpendicular force applied per unit area.
i.e. 
Now, 
where, 
= mass of the body(man) = 93 kg
= acceleration due to gravity of Earth = 9.81 
covered is equal to the area of both stilts(a man generally stands on two feet)
therefore 
and putting in the values, we get,
Now we need to convert to our required units:
(We can get the above result by individually converting kg to lb and meters to inches respectively)
Using the above relations we get,
Answer:
Explanation:
a )
Reaction force of the ground
R = mg
= 160 N
Maximum friction force possible
= μ x R
= μ x 160
= .4 x 160
= 64 N .
b )
160 N will act at middle point . 740N will act at distance of 3 / 5 m from the wall ,
Taking moment about top point of ladder
160 x 1.5 + 740 x 3/5 + f x 4 = 900 x 3
240 + 444 + 4f = 2700
f = 504 N
c )
Let x be the required distance.
Taking moment about top point of ladder
160 x 1.5 + 740 x 3 x / 5 + .4 x 900 x 4 = 900 x 3 ( .4 x 900 is the maximum friction possible )
240 + 444 x + 1440 = 2700
x = 2.3 m
so man can go upto 2.3 at which maximum friction acts .
