# physics

A car traveling at 53 km/h hits a bridge abutment. A passenger in the car moves forward a distance of 65 cm (with respect to the road) while being brought to rest by an air bag. What magnitude of foce (assume constant) acts on the passengers's upper torso, which is 41 kg?

I changed 65 cm into .00065 km. I think i need to use F=ma so I need to find a. To find a I used d =1/2 (v0+v)t to find time and I got 2.45X10^-5. then I used a = v/t and i got 2163265.31 as a. Then i pluged m and a into F=ma and I got 88693877.71 for the answer. Is this correct? I wouldn't think the force would be this high.

Why not use

force*distance= 1/2 mass*velocity^2

That is the work done on the bag is equal to the change in KE of the passenger.

You should get the same answer as your technique, but I suspect the teacher was exploring the energy relationships in motion, as I laid out.
For information:

force*distance= 1/2 mass*velocity^2

force*distance= 1/2 mass*(avgveloctity*2)^2

force*distance= 2 mass*(avgveloctity )^2

force*avgvelociy*time= 2 mass*(avgveloctity )^2

force = 2 mass*(avgveloctity )/time

force = mass*(2avgveloctity )/time

force= mass*acceleration as you started from.

1. 👍 0
2. 👎 0
3. 👁 249
1. Must use meters, not kilometers.

1. 👍 0
2. 👎 0
posted by Robert

## Similar Questions

1. ### Physics

A car traveling at 71 km/h hits a bridge abutment. A passenger in the car moves forward a distance of 63 cm (with respect to the road) while being brought to rest by an inflated air bag. What magnitude of force (assumed constant)

asked by Kaley on March 3, 2016
2. ### Physics

A car traveling at 50 km/h hits a bridge abutment. A passenger in the car moves forward a distance of 74 cm (with respect to the road) while being brought to rest by an inflated air bag. What magnitude of force (assumed constant)

asked by Oriana on December 12, 2010
3. ### physics

A car traveling at 69 km/h hits a bridge abutment. A passenger in the car moves forward a distance of 59 cm (with respect to the road) while being brought to rest by an inflated air bag. What magnitude of force (assumed constant)

asked by John on September 28, 2009
4. ### Physics

A car traveling at 58 km/h hits a bridge abutment. A passenger in the car moves forward a distance of 63 cm (with respect to the road) while being brought to rest by an inflated air bag. What magnitude of force (assumed constant)

asked by Leo on March 6, 2012
5. ### physics

A car traveling at 62 km/h hits a bridge abutment. A passenger in the car moves forward a distance of 58 cm (with respect to the road) while being brought to rest by an inflated air bag. What magnitude of force in newtons (assumed

asked by Mary on March 7, 2011
6. ### physics

A car travelling at 60 km/h hits a bridge abutment. A passenger in the car moves forward a distance of 67 cm (with respect to the road) while being brought to rest by an inflated air bag. What force (assumed constant) acts on the

asked by gregory on September 27, 2014
7. ### physics

A car is traveling at 25m/s when an accident occurs. The car decelerates 300m/s^2 but the passenger does not slow down because he is not wearing a seatbelt. a) Supposing the distance between the passenger and the dashboard is

asked by rob on February 10, 2013
8. ### Algebra

While traveling in a car, the centrifugal force a passenger experiences as the car drives in a circle varies jointly as the mass of the passenger and the square of the speed of the car. If the a passenger experiences a force of

asked by Anonymous on March 16, 2010
9. ### Physics

A car is traveling on a level horizontal rode comes to a bridge during a storm and finds the bridge washed out. The driver must get to the other side, so he decides to try leaping it with his car. The side of the road the car is

asked by Mark on March 22, 2017
10. ### Physics

A car is traveling on a level horizontal rode comes to a bridge during a storm and finds the bridge washed out. The driver must get to the other side, so he decides to try leaping it with his car. The side of the road the car is

asked by mark on March 22, 2017

More Similar Questions