Answer:
Explanation:
a )
moment of inertia of hollow ball
= 2 / 3 mR² , m is mass and R is radius of the ball
= 2 / 3 x 120 x .5²
= 20 kg m²
b )
5 rpm = 5 / 60 rps
n = .0833
angular velocity ω = 2πn= 2 x 3.14 x .0833= .523 rad /s
angular acceleration = increase in angular velocity / time
= .523 - 0 / 20
α = .02615 rad /s²
c )
Torque = moment of inertia x angular acceleration
= 20 x .02615
= .523 Nm
d )
θ = 1/2 α t²
= .5 x .02615 x 20²
= 5.23
2π n = 5.23 where n is required number
n = .83
Answer:
Distance, d = 99990 meters
Explanation:
It is given that,
Speed of the train, v = 200 km/h = 55.55 m/s
Time taken, t = 1800 s
Let d is the distance covered by the train. We know that the speed of an object is given by total distance covered divided by total time taken. Mathematically, it is given by :



d = 99990 m
So, the distance covered by the train is 99990 meters. Hence, this is the required solution.
Answer:
Your answer should be B. Cooled air
Explanation:
Yes the Earth is bigger than the Moon.
The moon is one-quarter the size of Earth.
I think there would be an increase in force of friction