Aball is thrown straight up into the air with an initial velocity of 50 ft/sec. the height h(t) of the ball after t seconds is given by latex: h\left(t\right)=50y-16t^2h ( t ) = 50 y − 16 t 2. what is the average velocity for the time period beginning when t=1 and lasting 0.1 seconds?

To understand the behavior of the electric field at the surface of a conductor, and its relationship to surface charge on the conductor. a conductor is placed in an external electrostatic field. the external field is uniform before the conductor is placed within it. the conductor is completely isolated from any source of current or charge. part a: which of the following describes the electric field inside this conductor? it is in the same direction as the original external field.it is in the opposite direction from that of the original external field.it has a direction determined entirely by the charge on its surface.it is always zero. part b: the charge density inside the conductor is: 0non-zero; but uniformnon-zero; non-uniforminfinite part c: assume that at some point just outside the surface of the conductor, the electric field has magnitude e and is directed toward the surface of the conductor. what is the charge density η on the surface of the conductor at that point? express your answer in terms of e and ϵ0

What is the efficiency of an engine that does 80 j of work and exhausts 320 j of heat while taking in 400 j of heat ? a. 10% b. 20% c. 80% d. 25%

Aforce f making an angle with the horizontal is acting on an object resting on the table. which statement is true for the motion of sliding the object on the table?