A lorry with a mass of 210 has a tractive resistance of 280N/t at a speed of 72km/h .calculate the distance covered in 36s and the power required for that speed
210 whats ?
N/t is what? Newtons per ton or something?
anyway
power in watts = force in Newtons * velocity in meters per second
distance = speed * time,
remember 3600 seconds / hr and 1000 meters / km
To calculate the distance covered in 36 seconds, we need to convert the speed from km/h to m/s.
Given:
Mass of the lorry (m) = 210 t (tonnes)
Tractive resistance (R) = 280 N/t
Speed (v) = 72 km/h
Step 1: Convert the mass from tonnes to kg.
1 tonne = 1000 kg
Mass (m) = 210 t = 210 × 1000 kg = 210000 kg
Step 2: Convert the speed from km/h to m/s.
1 km/h = 1000 m / 3600 s
Speed (v) = 72 km/h = (72 × 1000 m) / (3600 s) = 20 m/s
Step 3: Calculate the tractive force.
Tractive Force (F) = R × m
F = (280 N/t) × 210000 kg = 58800000 N
Step 4: Calculate the distance covered in 36 seconds using the formula: distance = speed × time.
Distance (d) = v × t
d = 20 m/s × 36 s = 720 meters
Therefore, the distance covered in 36 seconds is 720 meters.
Step 5: Calculate the power required at that speed using the formula: power = force × velocity.
Power (P) = F × v
P = 58800000 N × 20 m/s = 1,176,000,000 W
Therefore, the power required for that speed is 1,176,000,000 Watts.
To calculate the distance covered in 36 seconds, we need to convert the speed from km/h to m/s.
First, let's convert 72 km/h to m/s:
1 km/h = 0.27778 m/s
Thus, 72 km/h = 72 * 0.27778 = 20 m/s.
Now, to calculate the distance covered in 36 seconds, we can use the formula:
Distance = Speed * Time
Distance = 20 m/s * 36 s = 720 meters.
Next, let's calculate the power required for that speed. The power can be calculated using the formula:
Power = Force * Velocity
Given that the tractive resistance is 280 N/t (Newtons per ton) and the mass of the lorry is 210 tons, we need to convert the mass from tons to kilograms:
1 ton = 1000 kg
Thus, 210 tons = 210 * 1000 = 210,000 kg.
Now, we can calculate the power:
Power = Tractive Resistance * Velocity
Power = (280 N/t * 210,000 kg) * 20 m/s
Power = 5,880,000 N * m/s.
The unit of power is Watts (W), so the final answer is 5,880,000 W.
To summarize:
- The distance covered in 36 seconds is 720 meters.
- The power required for that speed is 5,880,000 Watts.