Ostriches go through a large change in body mass as they grow from hatchlings to adults. Body mass increases 25-fold as the bird develops from a four-week hatchling to a full grown adult. The duration of a reflex loop (time from stimulus to response) depends on the distance (length) the signals have to travel and the conduction velocity of action potentials along axons. If the conduction velocity is directly proportional to the cross-sectional area of axons(A) by what factor does the cross sectional area of the axon have to increase in order to maintain a constant reflex duration as the animal grows?(B) By what factor would the cross-sectional area of axons increase under isometric scaling.

Ogle–2013–blg–0723 is an exoplanet that is similar to earth in size and proximity to its star. this exoplanet has mass m=4.18×1024kg and radius r=5.66×106m. an astronaut whose weight on earth is w=735n lands on the planet. a. calculate m, the mass of the astronaut. b. calculate gp? , the acceleration due to gravity on the surface of ogle–2013–blg–0723. c. calculate wp? , the weight of the astronaut on the surface of ogle–2013–blg–0723. d. calculate v, the minimum velocity required to put an object into orbit above ogle–2013–blg–0723. e. calculate t, the time required to complete an orbit around ogle–2013–blg–0723.

To run the physics cart, the fan speed of the cart is manipulated. this is the (blank) variable. the cart accelerates due to the speed of the fan. acceleration is therefore the (blank) variable. a “constant” is a parameter that stays the same regardless of the variables. one parameter of the cart that is held constant is the (blank) .

A3.9 g aluminum foil ball with a charge of +4.1×10−9 c is suspended on a string in a uniform horizontal e⃗ field. the string deviates to the right and makes an angle of 30∘ with the vertical. part a part complete what information about the e⃗ field can you determine for this situation? what information about the field can you determine for this situation? only the magnitude of e⃗ only the direction of e⃗ both the magnitude and the direction of e⃗ none of the above previous answers correct part b determine the magnitude of the electric field. express your answer with the appropriate units. e e = nothing nothing request answer part c determine the direction of the electric field. determine the direction of the electric field. to the right to the left away from you toward you