When you start to construct a prototype machine, you find it is difficult to produce a 0.25-t magnetic field over such a large area. if you decrease the length of the bar to 0.20 m while leaving b, v, and r the same as in part a, what will be the power required of the person? express your answer using two significant figures.

We put a force of 50n on an object and the acceleration is 100 m/s². what is the mass of the object?

The rocket is fired vertically and tracked by the radar station shown. when θ reaches 66°, other corresponding measurements give the values r = 32700 ft, r¨ = 85 ft/sec2, and θ˙ = 0.019 rad/sec. calculate the magnitudes of the velocity and acceleration of the rocket at this position.

In a simplified model of the human eye, the aqueous and vitreous humors and the lens all have a refractive index of 1.40, and all the refraction occurs at the cornea, whose vertex is 2.60 cm from the retina. what should be the radius of curvature of the cornea such that the image of an object 40.0 cm from the cornea’s vertex is focused on the retina?