Answer: a) 0.78 m/s b) 1.57 m/s
Explanation:
M = father's mass
m = son's mass = M/3
V = father's initial speed
v = son's initial speed
(1/2)MV^2 = (1/2)*(1/2)*m v^2
M*V^2 = (1/2)(M/3)v^2
V^2/v^2 = 1/4
V = v/2
Second equation:
(1/2)M*(V + 1.4)^2 = (1/2)m*v^2
= (1/2)*(M/3)*(3V)^2
cancel out the M's and (1/2)'s
(V + 1.4)^2 = 3V^2
V^2 + 2.8V + 1.96 = 3V^2
V^2 -1.4V -0.98 = 0
V^2 = 0.98/0.4 = 2.45
V = 1.57
Answer:
Current, I = 0.0011 A
Explanation:
It is given that,
Diameter of rod, d = 2.56 cm
Radius of rod, r = 1.28 cm = 0.0128 m
The resistivity of the pure silicon, 
Length of rod, l = 20 cm = 0.2 m
Voltage, 
The resistivity of the rod is given by :


R = 893692.30 ohms
Current flowing in the rod is calculated using Ohm's law as :
V = I R


I = 0.0011 A
So, the current flowing in the rod is 0.0011 A. Hence, this is the required solution.
Answer:
A) The speed of the water must be 8.30 m/s.
B) Total kinetic energy created by this maneuver is 70.12 Joules.
Explanation:
A) Mass of squid with water = 6.50 kg
Mass of water in squid cavuty = 1.55 kg
Mass of squid = 
Velocity achieved by squid = 
Momentum gained by squid = 
Mass of water = 
Velocity by which water was released by squid = 
Momentum gained by water but in opposite direction = 
P = P'


B) Kinetic energy does the squid create by this maneuver:
Kinetic energy of squid = K.E =
Kinetic energy of water = K.E' = 
Total kinetic energy created by this maneuver:


Can neither be created or destroyed.