Final answer:
It takes 1 second for an object with a momentum of 20 kgm/s to come to a stop when a force of -20 N is applied. Impulse, equal to the momentum, divided by the force gives the time duration.
Step-by-step explanation:
The question asks how long it will take for an object with a momentum of 20 kgm/s to come to a stop when a force of -20 N is applied. To find the time, we can use the equation that relates force, change in momentum, and time, which is Impulse = Force × Time. Here, the impulse is the change in momentum, which in this case is the entire momentum of the object since it comes to a stop.
First, we identify the impulse as being equal to the momentum of the object, which is 20 kgm/s. Since the force applied is -20 N (the negative sign indicates that the force is acting in the opposite direction of the motion), we can set the impulse equal to the product of force and time to solve for time. The calculation would be as follows:
- Impulse = Momentum = 20 kgm/s
- Force = -20 N
- Time = Impulse / Force = 20 kgm/s / -20 N
- Time = -1 s (negative time implies that the action is in the opposite direction to the force applied)
The time it takes for the object to stop would be 1 second, but since time cannot be negative when we measure a duration, we consider only the magnitude of time which is 1 second. This is consistent with the principles of physics where time is scalar and has a positive value.