Answer:
576 joules
Explanation:
From the question we are given the following:
weight = 810 N
radius (r) = 1.6 m
horizontal force (F) = 55 N
time (t) = 4 s
acceleration due to gravity (g) = 9.8 m/s^{2}
K.E = 0.5 x MI x ω^{2}
where MI is the moment of inertia and ω is the angular velocity
MI = 0.5 x m x r^2
mass = weight ÷ g = 810 ÷ 9.8 = 82.65 kg
MI = 0.5 x 82.65 x 1.6^{2}
MI = 105.8 kg.m^{2}
angular velocity (ω) = a x t
angular acceleration (a) = torque ÷ MI
where torque = F x r = 55 x 1.6 = 88 N.m
a= 88 ÷ 105.8 = 0.83 rad /s^{2}
therefore
angular velocity (ω) = a x t = 0.83 x 4 = 3.33 rad/s
K.E = 0.5 x MI x ω^{2}
K.E = 0.5 x 105.8 x 3.33^{2} = 576 joules
Answer:
<h2>602.08 N</h2>
Explanation:
The force supplied by the train can be found by using the formula

w is the workdone
d is the distance
From the question we have

We have the final answer as
<h3>602.08 N</h3>
Hope this helps you
The gravitational field is the Force divided by the mass
Call g the gravitational fiel, F the force exerted by the earth and m the mass of the telescope.
g = F / m
g=9.1x10^4 N / 1.1 x 10^4 kg = 8.27 N/kg
Note that the unit N/kg is equivalent to m/s^2