1. how far from the home did karen and her mother travel during the first hour of the trip?

2. calculate the average speed of the car during the first hour of the trip.

3. how far did karen and her mother travel during the second hour of the trip?

4. calculate the average speed of the car during the first two hours of the trip.

5. identify the time period(s) during the trip when the car was traveling at the greatest average speed.

6. identify the time period(s) during the trip when the car was stopped.

7. calculate the average speed of the car for the first three hours of the trip.

8. if karen and her mother take three hours to come home, calculate the average speed of the car for the trip home.

1).  The first green circle on the graph, at 1 hr, is up at 40 miles.

2).  (40 miles) / (1 hour)  =  40 mph

3).  The distance doesn't change during the second hour.
     They didn't travel at all during that hour.

4).  Average speed = (distance covered) / (time to cover the distance)
                             =      40 miles           /          2 hours
                             =                    20 mph during the first 2 hours

5).  The greatest average speed is the period where the graph
has the steepest slope.  That's during the first hour.

6).  The car was stopped during the whole 2nd hour and the whole 5th hour.

7).  At the end of 3 hours, the graph has moved up to 60 miles.
The average speed during those 3 hours is

                     (60 miles) / (3 hours)  =  20 mph .

8).  The farthest away from home they ever got was 76 miles.
If they take 3 hours to return, over the same route, then their
average speed on the return will be

           (76 miles) / (3 hours)  =  (25 and 1/3) miles per hour.

    m₁v₁ + m₂v₂ = (m₁ + m₂)vmomentum is conserved.the left-hand side of the equation represents the momentum in the system before the collision.the right-hand side represents the momentum in the system after the collisionm₁ and v₁ represents the mass and the velocity of the physics blockm₂ and v₂ represents the mass and velocity of the ball of puttyv represents the final velocity of the combined mass.the question states the two masses stick together. they combined mass has its own velocity with the body mass the sum of the two objects' massestheir combined momentum is (m₁ + m₂)vto find the magitude of (m₁ + m₂)v, we need to add the vectors on the left-hand side of the equation: m₁v₁ + m₂v₂.note the diagram. i have positioned the vectors in accordance with their directions.the magnitude of the resultant can be calculated using the pythagorean theorem since this is a right triangle situation (north and west are perpendicular)|(m₁ + m₂)v| =  √[ (m₁v₁)² + (m₂v₂)² ]|(m₁ + m₂)v| =  √[ (1.5kg·8.0m/s)² + (0.40kg·20m/s)² ]|(m₁ + m₂)v| =  14.4 kg m/sfor two significant figures (assuming that 20m/s is two), this rounds to 14 kg m/s