What is the momentum of a 2000-pound car traveling at 30 miles per hour? Give the answer in metric units (change pounds to kilograms; miles per hour to meters per second).
Choose the best answer from the options below:
A 10,900
B 12,120
C 9,000
D 13,140
E 15,000
To find the momentum of the car, we need to convert the weight from pounds to kilograms and the speed from miles per hour to meters per second.
First, let's convert the weight from pounds to kilograms. There are 2.205 pounds in 1 kilogram. So, the weight of a 2000-pound car is (2000 pounds) / (2.205 pounds per kilogram) = 907.18 kilograms.
Next, let's convert the speed from miles per hour to meters per second. There are 0.447 m/s in 1 mile per hour. So, the speed of a car traveling at 30 miles per hour is (30 miles per hour) * (0.447 m/s per mile per hour) = 13.41 m/s.
The momentum of an object is calculated using the formula: momentum = mass * velocity. Therefore, the momentum of the car is (907.18 kg) * (13.41 m/s) = 12,154.46 Ns.
Rounding to the nearest whole number, the momentum of the car is approximately 12,154 Ns.
Therefore, the best answer is B 12,120.
To calculate the momentum of an object, we use the equation:
momentum = mass * velocity
First, we need to convert the mass of the car from pounds to kilograms.
1 pound = 0.4536 kilograms
Therefore, the mass of the car is:
2000 pounds * 0.4536 kilograms/pound = 907.2 kilograms
Next, we need to convert the velocity from miles per hour to meters per second.
1 mile = 1609.34 meters
1 hour = 3600 seconds
Therefore, the velocity of the car is:
30 miles/hour * 1609.34 meters/mile * 1 hour/3600 seconds = 13.4111 meters/second
Now, we can calculate the momentum:
momentum = mass * velocity
momentum = 907.2 kilograms * 13.4111 meters/second
Using a calculator, the answer is approximately 12,140.
Therefore, the correct answer is:
B) 12,120