Connecting forces and motion

Question 1

What is the resultant force of an object?

Answer 1

It is the sum of all the individual forces acting on the object, taking into account different directional forces subtract from one and other

Question 2

What is the formula for momentum?

Answer 2

momentum (kg m/s) = mass (kg) * velocity (m/s)

Question 3

What is the formula for change in momentum

Answer 3

change of momentum (kg m/s) = resultant force (N) * time for which it acts (s)

Question 4

What happens to a moving object if the driving force is: greater than the counter, equal to the counter force, smaller than the counter force?

Answer 4

If the driving force is larger than the counter force the object will speed up, if its the same the object’s speed will remain constant, if its smaller then the object will slow down

Question 5

What some features of a car or vehicle that are road safety measures?

Answer 5

Car seat belts, crumple zones, air bags, and bike and motorbike helments

Question 6

What is the purpose of these safety measures in terms of how they affect momentum in a crash?

Answer 6

They are all designed to increase the time of impact, by doing this the resultant force is decreased as they are multiplied to give the change of momentum (a fixed value in a crash)

Question 7

What effect does the resultant force of an object being 0 have on it;s momentum?

Answer 7

If the resultant force is 0 then the change in momentum is also 0, this means if the objects still it will remain still and moving objects will remain travelling at a constant velocity.