Why are objects measured?​

Basilisk lizards can run across the top of a water surface (see the figure). with each step, a lizard first slaps its foot against the water and then pushes it down into the water rapidly enough to form an air cavity around the top of the foot. to avoid having to pull the foot back up against water drag in order to complete the step, the lizard withdraws the foot before the water can flow into the air cavity. if the lizard is not to sink, the average upward impulse on the lizard during this full action of slap, downward push, and withdrawal must match the downward impulse due to the gravitational force. suppose the mass of a basilisk lizard is 93.7 g, the mass of each foot is 3.37 g, the speed of a foot as it slaps the water is 1.15 m/s, and the time for a single step is 0.531 as. (a) what is the magnitude of the impulse on the lizard during the slap

Sometimes questions that involve graphs will ask you to consider the effect of a changing factor or factors. problem​ statement: right arrow the line labeled d1 in the graph to the right shows the number of cups of lemonade that caroline and emily can sell at their lemonade stand at various prices. caroline and emily have noticed that they sell more lemonade when​ it's hotter. click anywhere on the graph to open a window with a control labeled temperature. if you use the slider to change the​ temperature, the line will shift. change the temperature from 80 degrees to 100 degrees. ​question: right arrow at a price of​ $0.50, how many more or fewer cups of lemonade do caroline and emily sell when the temperature is 100 degrees than when the temperature is 80​ degrees? ​(note: indicate the change in cups of lemonade​ sold: fewer will be a negative number and more will be a positive​ number)

7.45 a student is interested in the aerodynamic drag on spheres. she conducts a series of wind tunnel tests on a 10-cm-diameter sphere. the air in the wind tunnel is at 50 â°c and 101.3 kpa. she presents the results of her tests in the form of a correlation, đť’ź = 0.0015v1.92, where đť’ź is the drag force in newtons and v is the velocity in m/s. another student realizes that the results would have been more effectively presented in terms of dimensionless parameters, say, î  1 = f (î  2) = c î  a2 , where î  1 and î  2 are dimensionless parameters and c and a are constants. what are the most appropriate dimensionless parameters (î  1 and î  2) and the corresponding values of c and a? what would be the drag on a 2-cm-diameter sphere placed in a 1-m/s, 20 â°c water stream?