Answer:
The velocity of the train is 82.8 km/h
Explanation:
The equation for the position of the train and the car is as follows:
x = x0 + v · t
Where:
x = position at time "t".
x0 = initial position.
v = velocity.
t = time.
First, let´s calculate the distance traveled by the car in 60 s (1/60 h). Let´s place the origin of the frame of reference at the front of the train when it starts to pass the car so that the initial position of the car is 0 (x0 = 0 m):
x = 0 m + 72 km/h · (1/60) h
x = 1.2 km.
Then, if the whole train passes the car at that time, the position of the front of the train at that time will be 1.2 km + 0.18 km = 1.38 km.
Then using the equation of position we can obtain the velocity:
x = x0 + v · t
1.38 km = 0 m + v · (1/60) h
1.38 km / (1/60) h = v
v = 82.8 km/h
The velocity of the train is 82,8 km/h
The same result could be obtained using the rear of the train. You only have to identify where the rear is at t = 0 and where it is at t = 60 s.
Try it!
Answer:
Explanation:
This problem is based on conservation of angular momentum.
moment of inertia of larger disc I₁ = 1/2 m r² , m is mass and r is radius of disc . I
I₁ = .5 x 20 x 5²
= 250 kgm²
moment of inertia of smaller disc I₂ = 1/2 m r² , m is mass and r is radius of disc . I
I₂ = .5 x 10 x 2.5²
= 31.25 kgm²
3500 rmp = 3500 / 60 rps
n = 58.33 rps
angular velocity of smaller disc ω₂ = 2πn
= 2π x 58.33
= 366.3124 rad /s
applying conservation of angular momentum
I₂ω₂ = ( I₁ +I₂) ω , ω is the common angular velocity
31.25 x 366.3124 = ( 250 +31.25) ω
ω = 40.7 rad / s .
Answer:
Mass = 0.04 Kg
Explanation:
Given the following data;
Density = 800 kg/m³
Volume = 5 * 10^{-5} m³
To find the mass of the object;
Density can be defined as mass all over the volume of an object.
Simply stated, density is mass per unit volume of an object.
Mathematically, density is given by the formula;
Making mass the subject of formula, we have;
Substituting the values into the formula, we have;
Mass = 0.04 Kg
Explanation:
its hard to explain its very complex but its so they can function properly
