Answer:
Time=7.84hrs
Explanation:
This is an inverse proportionality questions
Mathematically time t varies as 1/distance d
Hence T= dk/r
But speed r = distance/t
d= r*t= 9*20=180km/hr
We're k= constant of proportionality
At t=9hrs d=180km/hr
Hence k=r*t/d=20*9/1620=0.111
Finding t at at 1620km for 23km/hr
t=1620*0.111/23=7.84hrs
Answer: 9kgm/s
Explanation:
Given that,
Mass of ball = 3 kg
Speed by which ball moves = 3 m/s. Linear momentum of the ball = ?
Since momentum refers to the quantity of motion of the moving ball,
Linear momentum = Mass x Speed
= 3kg x 3m/s
= 9 kgm/s
Thus, the linear momentum of the ball is 9kgm/s
All of the rivers in the United States are not monitored closely for pollution levels.
The statement in the question is False
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Explanation:</u></h3>
Not all rivers in the United States are closely monitored for their pollution levels. There are volunteers who take responsibility of checking water bodies such as lakes, rivers, streams etc. They take the next step required after finding a water body contaminated.
But to say that all the rivers receive the same amount of attention and action is incorrect. To ensure that all the rivers are clean and pollution free, it would require a lot of man power in the said department which would collect the water samples from all these rivers and send it to labs for checking the pollution level of the particular river. It can be said that the rivers which are situated beside an industrial site, close to a town, will be the priority for checking pollution levels as it would directly cause harm to a small set of population if the toxicity is at an increased level.
6: velocity i hpe this is what your looking for
Central maximum = d* wavelength/ D
thus
12*10-^3 = 3.4*6.32*10-^7/D
D = 3.4*6.32*10-^7/12*10-^3
D = 1.79*10-^4 m
