Pulleys are powerful simple machines. They can change the direction of a force, which can make it much easier for us to move something. If we want to lift an object that weighs 10 kilograms one meter high, we can lift it straight up or we can use a pulley, so we can pull down on one end to lift the object up.
Answer:
Explanation:
The acceleration of the bycicle is given by:
where
v = 20 m/s is the final velocity of the bike
u = 40 m/s is the initial velocity
t = 5 s is the time interval
Substituting numbers, we find
and the acceleration is negative, which means that the bycicle is slowing down.
Answer:
9.14hrs
Explanation:
1 horse power = 745.7 watts
1.5 horse power = 1118.55 watts
1 ft = 0.305 m
24 ft = 7.3152 m
60 ft = 18.288 m
the water tank is spherical, volume of a spherical tank = 3/4 πr³ where is r is the radius of the tank = 7.3152 m / 2 = 3.66 m
volume = 4/3 ( 3.66 m ³) × 3.142 = 205.394 m³
mass of water = density × volume = 205.394 m³ × 1000kg/m³ = 205,394 kg
weight of water = mass × acceleration due to gravity = 205,394 kg × 9.8 = 2012861.2 N
potential energy stored at the height where water was stored = mgh = weight × height = 2012861.2 N × 18.288 m
potential energy stored = energy from the pump = power in watt × t
1118.55 watts × t =2012861.2 N × 18.288 m
t = (2012861.2 N × 18.288 m) / 1118.55 watts = 32846.62 secs = 9.14 hrs
Answer:
I think it's dio to atmospheric pressure.