Answer:
255.34 J
Explanation:
Given,
Weight of disk = 805 N
radius = 1.47 m
Force applied by the child = 49 N
time = 2.95 s
KE = ?
mass of the disk

Moment of inertia of the disk


Torque on the child

Angular acceleration

So, angular speed at t = 2.95 s

Now, KE of the merry go round

Hence, the Kinetic energy of the merry go round = 255.34 J
Answer:
114.44 J
Explanation:
From Hook's Law,
F = ke................. Equation 1
Where F = Force required to stretch the spring, k = spring constant, e = extension.
make k the subject of the equation
k = F/e.............. Equation 2
Given: F = 10 lb = (10×4.45) N = 44.5 N, e = 4 in = (4×0.254) = 1.016 m.
Substitute into equation 2
k = 44.5/1.016
k = 43.799 N/m
Work done in stretching the 9 in beyond its natural length
W = 1/2ke²................. Equation 3
Given: e = 9 in = (9×0.254) = 2.286 m, k = 43.799 N/m
Substitute into equation 3
W = 1/2×43.799×2.286²
W = 114.44 J
Answer: Got It!
<em>Explanation: </em>let s = speed at launch
v = 0 at top = s sin 63 - g t
so at top
t = s sin 63/g = .0909 s
h = 13.6 = s sin 63 t - 4.9 t^2
13.6 = .081s^2 - .0405 s^2
s^2 = 336
s = 18.3 m/s
0 0
Venus is closer, relatively the same size as the earth and has an atmosphere