Answer:
(a) 1.257 x 10^5 J
(b) 1.456 Watt
Explanation:
Volume of blood, v = 7500 L = 7.5 m^3
Height, h = 1.63 m
density of blood, d = 1.05 x 10^3 kg/m^3
(a) work done = m x g x h
W = v x d x g x h = 7.5 x 1.05 x 1000 x 9.8 x 1.63 = 1.257 x 10^5 J
(b) time = 1 day = 24 x 60 x 60 s = 86400 seconds
Power = Work / time = 1.257 x 10^5 / 86400 = 1.456 Watt
Let's call
the mass of the glider and
the total mass of the seven washers hanging from the string.
The net force on the system is given by the weight of the hanging washers:
For Newton's second law, this net force is equal to the product between the total mass of the system (which is
) and the acceleration a:
So, if we equalize the two equations, we get
and from this we can find the acceleration:
Centripetal acceleration is directed along a radius so it may also be called the radial acceleration. If the speed is not constant, then there is also a tangential acceleration (at). The tangential acceleration is, indeed, tangent to the path of the particle's motion.
She can put chalk in vinegar as the vinegar will disintegrate the chalk chemically demonstrating chemical changes. But for physical changes she can break the chalk into small pieces by smashing it with something or her hand.