A person travels by car from one city to another with different constant speeds between pairs of cities. She drives for 15.0 min at 80.0 km/h, 15.0 min at 50.0 km/h, and 50.0 min at 45.0 km/h and spends 50.0 min eating lunch and buying gas. Determine the average sped for the trip. Determine the difference between the intial citties along the route.

Which object is most likely represented by a dot?

How many milliliters of water at 23 °c with a density of 1.00 g/ml must be mixed with 180 ml (about 6 oz) of coffee at 95 °c so that the resulting combination will have a temperature of 60 °c? assume that coffee and water have the same density and the same specific heat. how much will the temperature of a cup (180 g) of coffee at 95 °c be reduced when a 45 g silver spoon (specific heat 0.24 j/g °c) at 25 °c is placed in the coffee and the two are allowed to reach the same temperature? assume that the coffee has the same density and specific heat as water. a 45-g aluminum spoon (specific heat 0.88 j/g °c) at 24 °c is placed in 180 ml (180 g) of coffee at 85 °c and the temperature of the two become equal. (a) what is the final temperature when the two become equal? assume that coffee has the same specific heat as water. (b) the first time a student solved this problem she got an answer of 88 °c. explain why this is clearly an incorrect answer.

An olympic runner leaps over a hurdle. the acceleration of gravity is 9.81 m/s2 . if the runner’s initial vertical speed is 2.0 m/s, how much will the runner’s center of mass be raised during the jump?