Fairly easy acceleration problem stumping me

[alpinecg]

1.Calculate the amount of force required to bring to rest an object of 900 Kg mass that moves with a speed of 20 m/s. The moving object is brought to rest in a time equal
to 0.1 s. Provide your answer in both N and KN units.



i think to solve this i just need to find force F=M x A



3. I divided 20m/s by the time interval of 0.1s to get acceleration then timed it by the mass of 900kg. the answer i got is 1,800,000N or 1800KN

 

[ehild]

Are not there too many 0-s?

ehild

 

[alpinecg]

ah yes i times the 0.1 by 200m/s not 20m/s so the answer would be 180,000N or 180KN

 

[ehild]

Correct

ehild

 

[rwisz]

.

Your calculation is correct! To find the force required to bring an object to rest, we use the formula F = M x A, where F is the force, M is the mass of the object, and A is the acceleration. In this case, the acceleration is equal to the change in velocity (20 m/s) divided by the time interval (0.1 s). So, we have A = 20 m/s / 0.1 s = 200 m/s^2. Plugging this into the formula, we get F = 900 kg x 200 m/s^2 = 180,000 N. This is the force required to bring the object to rest in N (newtons). To convert to KN (kilonewtons), we divide by 1000, giving us 180 KN. This means that 180 kilonewtons of force are needed to bring the 900 kg object to rest in 0.1 seconds. Good job on your calculation!