Answer:
Angular displacement before it stops = 18 rev
Explanation:
Given:
Speed of fan w(i) = 6 rev/s
Speed of fan (Slow) ∝ = 1 rev/s
Final speed of fan w(f) = 0 rev/s
Find:
Angular displacement before it stops
Computation:
w(f)² = w(i) + 2∝θ
0² = 6² + 2(1)θ
0 = 36 + 2θ
2θ = -36
Angular displacement before it stops = -36 / 2
θ = -18
Angular displacement before it stops = 18 rev
Because other scientists and science in general rely on their collegues' research which in turn allows development of our knowledge on the given subject. The more dont-to-earth reason may be safety. If someone performs an experiment without knowledge of its true results it might result in some danger to the safety of those perforning it without knowledge of all the risks.
To calculate the distance to a star, astronomers observe it from different places along Earth's orbit around the Sun. If they measure the object's position several months apart, their "two eyes" will have a separation of well over 100 million miles!
C.
The range of temperatures on Earth allows water to exist in all of its states.
Answer:
The power of the pump is 337.5 W.
Explanation:
Power is the rate of transfer of energy or the rate at which work is done. It is measured in watts (W).
Power = 
But the energy here is the kinetic energy (K.E), which is the energy possessed by a moving body or object.
K.E = 
m
where m is the mass = 90 kg and v is the velocity = 15 m/s.
K.E = × 90 × 
= 10125 Joules
K.E = 10125 J = 10.125 KJ
So that the power of the pump when t = 30 s is;
Power = 
= 337.5 W
The power of the pump is 337.5 W.
