Answer:
b. 4.6 m/s
Step-by-step explanation:
the formula for calculating the linear velocity is expressed as;
v = wr
w is the angular velocity
r is the radius
r = d/2 = 18/2
r = 9 m
Given that 1rev/min = 0.10472rad/s
4.9 rev/min = x
x = 4.9 * 0.10472
x = 0.513128 rad/s
Substitute into the given formula;
v = 9 * 0.513128
V = 4.61m/s
Hence the velocity of the child in m/s is 4.6m/s