Which has the greater momentum when they move at the same speed- an automobile or a skateboard? Which requires the greatest stopping force?
the more mass and volume moving at a rate as something else smaller or more lightweight is going to need something of equal size and force to counter the momentum
ex. which would be easier to stop if launched at the same speed at you, a water melon or a tennis ball?
To determine which object has greater momentum when they move at the same speed, we need to calculate the momentum of each object.
The momentum of an object is calculated by multiplying its mass (m) by its velocity (v). The formula for momentum is:
Momentum = mass × velocity
Let's compare an automobile and a skateboard:
1. Momentum comparison:
- Automobile: Automobiles are generally much heavier than skateboards, so they will have a greater mass. Let's assume the mass of the automobile is 1000 kg (just for comparison purposes).
- Skateboard: Skateboards are much lighter, so let's assume the mass of the skateboard is 5 kg.
Assuming both the automobile and skateboard are moving at the same speed (let's say 10 m/s), we can calculate their momenta.
Momentum of the automobile = mass × velocity = 1000 kg × 10 m/s = 10,000 kg m/s
Momentum of the skateboard = mass × velocity = 5 kg × 10 m/s = 50 kg m/s
Therefore, the automobile has a greater momentum when they move at the same speed.
2. Stopping force comparison:
The stopping force required to bring an object to a stop depends on its momentum.
The formula to calculate the stopping force (F) is:
Stopping force = change in momentum / time
Since we assume both the automobile and skateboard are moving at the same speed, their velocities are the same. As a result, the change in momentum will be the same when brought to the same speed to stop.
However, the stopping force required for an object depends not only on its momentum but also on other factors such as the surface area in contact with the ground and the friction between the object and the surface. In this case, the automobile would require a greater stopping force compared to the skateboard due to its greater mass, higher inertia, and potentially larger surface area in contact with the ground.
So, to summarize:
- The automobile has greater momentum when moving at the same speed compared to the skateboard.
- The automobile would generally require a greater stopping force compared to the skateboard.