Answer:
1.25 kgm²/sec
Explanation:
Disk inertia, Jd =
Jd = 1/2 * 3.7 * 0.40² = 0.2960 kgm²
Disk angular speed =
ωd = 0.1047 * 30 = 3.1416 rad/sec
Hollow cylinder inertia =
Jc = 3.7 * 0.40² = 0.592 kgm²
Initial Kinetic Energy of the disk
Ekd = 1/2 * Jd * ωd²
Ekd = 0.148 * 9.87
Ekd = 1.4607 joule
Ekd = (Jc + 1/2*Jd) * ω²
Final angular speed =
ω² = Ekd/(Jc+1/2*Jd)
ω² = 1.4607/(0.592+0.148)
ω² = 1.4607/0.74
ω² = 1.974
ω = √1.974
ω = 1.405 rad/sec
Final angular momentum =
L = (Jd+Jc) * ω
L = 0.888 * 1.405
L = 1.25 kgm²/sec
Force = mass * acceleration
10 N - 2 N = 20 kg * acceleration
8 N = 20 kg * acceleration
8 / 20 = acceleration
2/5 m/s^2 = acceleration
Answer:
The distance between knothole and the paint ball is 0.483 m.
Explanation:
Given that,
Height = 4.0 m
Distance = 15 m
Speed = 50 m/s
The angle at which the forester aims his gun are,




Using the equation of motion of the trajectory
The horizontal displacement of the paint ball is


Using the equation of motion of the trajectory
The vertical displacement of the paint ball is



Put the value into the formula


We need to calculate the distance between knothole and the paint ball



Hence, The distance between knothole and the paint ball is 0.483 m.
156.8 Joules of energy is in the box's gravitational potential energy store
<u>Explanation</u>:
<em>Given:</em>
Mass of the box Dane is holding = 8 Kilograms
Height at which Dane is holding the box above the ground= 2 metres
<em>To Find:</em>
Gravitational potential energy in the box=?
<em>Solution:</em>
gravitational potential energy is the work done per mass on a object to move that object from one fixed location to to another location against gravity.Its unit is joules or J
Thus Gravitational potential energy is represented as,

where
is the gravitational potential energy
m is the mass
h is the height
g is the gravitational force( 9.8
)
Now substituting the given values,

