A 3600 kg open railroad car coasts along with a constant speed of 11.0 m/s on a level track. Snow begins to fall vertically and fills the car at a rate of 3.70 kg/min.
Ignoring friction with the tracks, what is the speed of the car after 80.0 min?
conservation of momentum
Momentum before= momentum after.
3600*11=masssnow*0= (3600+masssnow)Vf
masssnow= 3.7*80 kg
solve for Vf.
typo:
3600*11+masssnow*0=(3600+masssnow)*Vf
I hate that key,my pinky always misses +
To find the speed of the car after 80 minutes, we need to take into account the mass of the snow that has accumulated in the car.
First, we need to find the mass of the snow that has accumulated in 80 minutes. Since the snow is falling vertically and filling the car at a rate of 3.70 kg/min, we can multiply the rate by the time to find the total mass of the snow:
Mass of snow = Rate × Time
Mass of snow = 3.70 kg/min × 80 min
Mass of snow = 296 kg
Next, we can find the total mass of the car and the snow combined:
Total mass = Mass of car + Mass of snow
Total mass = 3600 kg + 296 kg
Total mass = 3896 kg
Now, we can use the law of conservation of momentum to find the final speed of the car. According to the law of conservation of momentum, the initial momentum of the car should be equal to the final momentum of the car and the snow combined. Since the car is coasting along with a constant speed, its initial momentum is given by:
Initial momentum = Mass of car × Initial velocity
And the final momentum is given by:
Final momentum = Total mass × Final velocity
Since the initial momentum is equal to the final momentum, we can set the two equations equal to each other and solve for the final velocity:
Mass of car × Initial velocity = Total mass × Final velocity
Rewriting the equation, we get:
Final velocity = (Mass of car × Initial velocity) / Total mass
Plugging in the known values:
Final velocity = (3600 kg × 11.0 m/s) / 3896 kg
Final velocity = 10.2 m/s
Therefore, the speed of the car after 80 minutes is 10.2 m/s.