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
Diameter = 0.170 meter
Circumference = 0.170 π meters
530 rpm = 530 circumferences / minute
= (530 x 0.170 π meters) / minute
= 283.06 meter.minute
= 4.72 meters/second
- Speed is the rate of change of distance with time while velocity is the rate of change of displacement with time.
- Speed is a scalar quantity while velocity is a vector quantity.
- Speed cannot be negative but velocity can be negative.
Hope you could get an idea from here.
Doubt clarification - use comment section.
There are two general types of collisions, inelastic and elastic.
Inelastic collisions occur when two objects collide but neither of them bounce away from each other.
Collisions in which the objects do not touch each other are elastic. (Ex: Rutherford Scattering)
