"Some microbes<span> are used for medicinal production. One of the most important groups of medicines, antibiotics, is produced by fungi and bacteria. The name antibiotics means 'against life'. It is appropriate, because they attack bacteria and other unicellular organisms that are pathogenic for </span>humans<span>."
hope this helps you!</span>
Answer:
C) less than 129 lb.
Explanation:
Let the elevator be slowing up with magnitude of a . That means it is accelerating downwards with magnitude a .
If R be the reaction force
For the elevator is going downwards with acceleration a
mg - R = ma
R = mg - ma
R measures its apparent weight . Spring scale will measure his apparent weight.
So its apparent weight is less than 129 lb .
Power = (force) x (distance / time) = force x speed .
We know the force = 800N.
We have a speed = 30km/hr, but in order to use it in the power formula,
it has to be in meters/second, so we have some work to do first.
(30 km/hr) x (1,000 m/km) x (1 hr / 3,600 sec) = 300 / 36 m/sec .
Power = (force) x (speed) = (800 N) x (300/36 m/s) = <em>6-2/3 kilowatts </em>
Work = (power) x (time) = (6,666-2/3 joule/sec) x (25sec) = <em>166,666-2/3 joules</em>.
The figure for power is slightly weird ... 746 watts = 1 horsepower,
so the truck's engine is only delivering about 8.9 horsepower.
Very fuel-efficient, but I don't think they drive trucks that way.
Answer
given,
radius of each hose = 0.025 m
water enters hydrant at radius = 0.075 m
speed of water in the pipe = 3.1 m/s
a) mass of water per hours through the house can be calculated
b) Using continuity equation
v₂ = 9.3 m/s
speed of water through each hose.
1 gram = 1/1000 kg. So 5000 g = 5 kg, so your answer is C.
